This is the tab for the full 9-minute masterpiece - I think there's a 4-minute single 
around somewhere but I doubt that affects the tab.
Ok, so this has pretty much the same bassline throughout.
He might start throwing in a few extra notes towards the end, but (if they actually 
they don't change the groove or anything.

Main part: (after two beat drum intro)
G|------------11-|---9-----------|---------------|--------------:|
D|---------------|-------9-------|---7--9------9-|---7----------:|
A|-9----7--------|---------7-----|-7-------------|------9-5-----:|
E|---------------|---------------|---------------|--------------:|

When played on its own (i.e. not playing along to the record), the last note sounds like 
should be a 'B'.
But, it sounds to me (especially in the bit directly after the drum solo) that he 
hits a 'D'.
Then again, there are also times in the song when it sounds like a 'B'.
But to be honest, it doesn't make much difference. Do whatever sounds best.

Ok, so he plays that until 3.42, when the last two bars become:
G|---------------|------------------|
D|---7--9------9-|------------------|
A|-7-------------|-9--------2---2---|
E|---------------|------------------|

Then there's the interlude bit:
G|------------|
D|-5----------|
A|-----5------|
E|------------| x2

Drum/percussion solo from 3.58 - 4.26
Then it's back to the main riff until the fade-out
Feel free to ad lib. a bit towards the end/ add some fills

Any comments/corrections really welcome
Great bassline. Great song