For full tab score layout, use the .tg file and load into TuxGuitar (free download).  

Bass comes in 15th bar with riff below played 4 times.

G|-----------------|--------|
D|-----------------|--------|
A|-5-5-------------|--------|
E|-----------------|--------|
   1 + 2 + 3 + 4 +

Then this riff is played 8 times

G|-----------------|-----------------|-----------------|--------|
D|-----------------|-----------------|-----------------|--------|
A|-5-5-------------|-----------5-----|-5-5-------------|--------|
E|-----------------|-----------------|-----------------|--------|
   1 + 2 + 3 + 4 +   1 + 2 + 3 + 4 +   1 + 2 + 3 + 4 +

Then riff 1 is played once then moves into this where you hold the second note on the first bar. The next 8 bars start out soft and gradually get louder.

G|-----------------|-------------------------------|----------------------------|-----------------------------|
D|-----------------|-------------------------------|----------------------------|-----------------------------|
A|-5-5-------------|-5—-5—-5-5-5-5-5-5-5-5-5-5-5-5-|-1--1--1--1-1-1--1-1-1--1-1-|-1--1-1-1--1-1-1--1-1-1--1-1-|
E|-----------------|-------------------------------|----------------------------|-----------------------------|
   1 + 2 + 3 + 4 +   1  +  2   +   3   +   4   +     1  +  2  +   3  +   4  +     1  +   2  +   3  +   4  +     

G|----------------------------|-----------------------------|-------------------------|---------------------------|
D|----------------------------|-----------------------------|-------------------------|---------------------------|
A|----------------------------|-----------------------------|-6--6--6--6--6--6--6--6--|-6--6--6--6----6------5----|
E|-3--3--3--3-3-3--3-3-3--3-3-|-3--3-3-3--3---3--3-3-3--3-3-|-------------------------|---------------------------|
   1  +  2  +   3  +   4  +     1  +   2  +   3  +   4  +     1  +  2  +  3  +  4  +    1  +   2  +   3  +   4  +   

From here John just plays variations on that riff.  He plucks sixteenths during the middle bit with the arpeggio.
At the end he plays these 2 riffs.  Riff 1 8 times, Riff 2 once, Riff 1 once, then Riff 2 8 times.


G|----------------------------|         G|----------------------------|
D|----------------------8--8--| Riff 1  D|----------------------8--8--| Riff 2
A|-6--6-6-6--6-6-6--6-6-------|         A|-7--7-7-7--7-7-6--6-6-------|
E|----------------------------|         E|----------------------------|
   1  +   2  +   3  +   4  +               1  +   2  +   3  +   4  +