The years: come and gone, but the memory lives on
How rock music could make me not gloomy
If I had my chance to make sad people dance
Then some gals might perchance want to do me
But came February: swore I couldn't take one step more
From the newspaper headlines: felt empty
Don't know if I cried when I read: widowed bride
And three pals we remember died early
My Chevy, we'd ride; got to the levee, but dried
Good ol' boys, from their still, would dispense some
As moon-shine whiskey flows, take a swig; raise a toast!
Miss Amer-ican Pie was quite pleasin'
With God, come to terms, as the Book of Love confirms
Left bereft, rock and roll, you believe in?
Can music make right, when soul: guilt, felt pang?
Can you teach me to slow-dance with feeling?
The Jester inspires: for the King and Queen, sang
Elvis: rave; Rock, though, was prevailing 
John Lennon and crew, in park, practiced a few
Singing dirge of disaster, we're reeling
So drawn by hate, came the murders: Sharon Tate 
Men, assailants from Manson cult, slashing
Byrds: after-nuke cave; cast was easing pain  
In first place, was the British Invasion 
We gathered, place, same: fam'ly book lost (Star Trek™?) 
All were mellow; none too rough, 'spite med'ia
It's said: had no time: a new pathway, begin
Then The Devil, with sin, blood, would show ya
So, Jack, be nimble, and ... holy water, cleanse your sin 
Devil's worship puts you all in peril
The sacrifice rite, on that night, the flames would light
Their Satanic Majestic Quest, caroled
Does anyone know why Hell's Angels guard shows? 
When the moods turn from peaceful to sour
But watching that stage, were my fists clenched in rage
I saw Satan was smiling, delighted
With knife, one slit up; the guy gun-waving dies 
The concert was deep in disorder
The venue was changed, and the stage was rearranged 
Cost a life; 'haps contributed: slaughter
An era tolls, but still, we all sing
The undoing: Miss American Pie, gone
Those good ol' boys seem like a long-lost dream
"Bye, bye!": fans; three boys, take Four Horsemen 
A lady I know walked on, very slow
Good news sought; ache; dreary news, render
Lovers' cryin'; kids: woe, as no merriment, they know
Poet's tales: dreams, forever engender
Went to musical hall; no result; none played
Bad-luck paradigm: roll, hexahedral 
No church bell chime; it had been broken: long time
Coast train: men I admire and herald
Their legends live on; from the Fifties, they hand down:
An orig' take for all; niche, regrooming
But cheerier; instead of our grief that they're dead
We'll all hail and remember them, surely
Using (and agreeing with) most common OS interpretation: that the King in TOS was the *original* King of Rock, Elvis himself, but the new sounds exemplified by Bob Dylan (referred to as "the Jester", both for his sometimes-clown-like outfits, and for the presence of jesters, clowns, etc. in his songs - check out the "jugglers and clowns" line in Dylan's "Like A Rolling Stone"), the Beatles, et al., were knocking Elvis off the charts. (The "Queen" is thought to refer to Little Richard, an acknowledged bisexual.)
An alternate interpretation is that this OS line refers to the Kennedys -- the King and Queen of "Camelot" -- who were present at a Washington, D.C. civil rights rally at which Dylan performed. But that doesn't explain
"While the King was looking down, the Jester stole his thorny crown"
JFK had his "crown" taken by assassination, but among all of the conspiracy theories out there, I don't remember Bob Dylan ever being mentioned as a suspect. ;)
 "Helter Skelter": the name that convicted killer Charles Manson gave to his scenario for apocalyptic war, which motivated his cult "family" for the murders of actress Sharon Tate (eight and a half months pregnant) and others. Manson was obsessed with The Beatles; got the name from their song by that name; and the words "helter skelter" were written in blood on the refrigerator in the home where the murders occurred..
 Hoped this was self-explanatory, but just in case: "after-nuke cave" = The Byrds' *fallout shelter*.
 "... with the Jester on the sidelines in a cast".
On July 29, 1966, Dylan crashed his motorcycle. Many biographers believe that the crash offered Dylan the much-needed chance to escape from the pressures that had built up around him due to his success. He withdrew from the public, saying "I had a family and I just wanted to see my kids" -- something that his hectic tour schedule had not permitted. So the cast, and the period of rest, eased his emotional pain as well as his physical.
 Continuing the theme started in :
"The players (of the early sounds of Rock) tried to take the field;
"The marching band refused to yield" - "Sgt. Pepper's Lonely Hearts Club Band", i. e., the Beatles, and by extension, the rest of the British Invasion of 1960s American rock, refused to yield their commanding position on the rock charts to the early pioneers like Elvis.
"There we were, all in one place" = Woodstock festival, summer of 1969.
"A generation, lost in space" (OK, that's a different TV show and movie from Star Trek, but it doesn't rhyme/match to OS "deck".) ... That generation was unsure of their place ("lost", figuratively), and the Woodstock concert was held only a few weeks after Apollo 11 successfully landed men on the Moon. ("in space") .... Third line = "With no time left to start again".
During the first few days of the festival, national media coverage emphasized the problems, including traffic and mud from the rain. Coverage became more positive by the end of the festival, in part because the parents of concertgoers called the media and told them, based on their children's phone calls, that their reporting was misleading.
A reporter for The New York Times asserted that he was pressured by editors to write a misleadingly-negative article about the event. He threatened to refuse to write the article until the paper's executive editor agreed to let him write the article as he saw fit. The eventual article dealt with issues of traffic jams and minor lawbreaking, but went on to emphasize cooperation, generosity, and the good nature of the festival-goers. When the festival was over, he wrote another article about the exodus of fans from the festival site and the lack of violence at the event. The chief medical officer for the event and several local residents were quoted as praising the festival-goers.
Compare this to the highly-contrasting event referred to later, in both OS and parody.
 (Covers the entire verse)
The "Jack be nimble" couplet in TOS is a reference to the 1968 Rolling Stones album, "Jumpin' Jack Flash".
From the Stones' 1967 album, "Their Satanic Majesties Request", and for other reasons (drug use, or a thousand others?), McLean refers to Mick Jagger and The Stones as "Devil" and "Satan". (Keeping in mind McLean's apparent Catholicism - the three men he admired most were The Father, Son, and The Holy Ghost, right?)
On December 6, 1969, The Rolling Stones organized and appeared at a free concert at Northern California's Altamont Speedway. Members of the infamous motorcycle gang, Hell's Angels, were invited. Stories differ on whether they were supposed to police the entire crowd; merely guard the equipment, or just sit at the edge of the stage and drink beer, making sure no one rushed the stage. The last theory has the most support. Their beer was allegedly paid for by the Stones' road manager.
Bad idea -- with both the crowd and the "guards" high on *something* (alcohol, LSD, etc.), there was one death, three serious accidents, and numerous instances of theft and vandalism. (And, uh, four *births* -- probably not the Angels' fault there. ;)
Hence OS line, "No Angel born in Hell could break that Satan's spell" -- Jagger's mesmerizing influence and incitement, presumably.
 An eighteen-year-old male, Meredith Hunter, tried to get onstage, along with other fans. One of the Angels punched him and chased him back into the crowd. Hunter returned, pulling a gun from his pocket, looking "crazy" to others, with apparent intent to harm Jagger or someone else on stage. An Angel rushed him with a knife, blocked his gun arm, and stabbed him to death. The Angel was charged with homicide, but the incident was accidentally caught on film, and seeing the film, the jury acquitted due to self-defense (or defense of innocent others). Autopsy showed Hunter was very high on methamphetamine.
The concert originally was scheduled at Golden Gate Park in San Francisco, but a conflicting football game caused it to be moved to the Sears Point Raceway. After a dispute with Sears Point's owner, the festival was moved to the Altamont Raceway. Huge difference: the Sears Point location would have had the stage at the *top* of a hill, making it harder to rush the stage. At Altamont, the stage was at the *bottom* of the slope, not only making stage-crashing easier, but meaning that any pushing toward the stage by the crowd would force innocent viewers along with them.
The violent event was seen by critics as contrasting to the "peace and love" attitude of Woodstock, and as signaling the end of the "hippie" culture and of the 1960s culture in general. Such a pivotal point surely influenced McLean heavily in composing his history (TOS), not only of the deaths of the young pioneers (Buddy Holly, Ritchie Valens, and J. P. Richardson, a/k/a "The Big Bopper"), but of the entire seminal era of Rock and Roll.
 Four Horsemen of the Apocalypse (Revelation 6: 1 - 8), used here as a general metaphor for tragedy or disaster.
 "hexahedral" - "describing a solid figure having six faces, as a cube".
In English: "This was the ultimate example of an unlucky roll of the dice." (the fatal plane crash commemorated by TOS)