Standard Tuning

First Riff

G---------------------------------------------
D--------------1---1-----3--------------------
A--3---3---3-----1---1-3----------------------
E----3---3---3--------------------------------

Followed by

G---------------------------------------------
D---------------------------------------------
A--3--3-3-3--3-3-3-3-6--6-6-6--6-6-6-6--------
E---------------------------------------------

Then

G---------------------------------------------
D---------------------------------------------
A---------------------------------------------
E--4-4-4-4-4-4-4-4-3-3-3-3-3-3-3-3------------

G---------------------------------------------
D---------------------------------------------
A--3-3-3-3-3-3-3-3-3-3-3-3-3-3-3-3------------
E---------------------------------------------

Variation

G---------------------------------------------
D---------------------------------------------
A---------------------------------------------
E--4-4-4-4-4-4-4-4-3-3-3-3-3-3-3-3------------

G---------------------------------------------
D---------------------------------------------
A--3-3-3-3-3-3-3-3-3-3-3--5s6-----------------
E---------------------------------------------

For the last few minutes the progression changes:

G---------------------------------------------
D---------------------------------------------
A--3-3-3-3-3-3-3-3-3-3-3-3-3-3-3-3------------
E---------------------------------------------

G---------------------------------------------
D---------------------------------------------
A---------------------------------------------
E--4-4-4-4-4-4-4-4-3-3-3-3-3-3-3-3------------

Then it variates after a while:

G---------------------------------------------
D---------------------------------------------
A--3-3-3-3-3-3-3-3-3---3---3-5-6--------------
E--------------------3---3--------------------

G---------------------------------------------
D---------------------------------------------
A---------------------------------------------
E--4-4-4-4-4-4-4-4-3-3-3-3-3-3-3-3------------

Then for the last bit it changes again:

G---------------------------------------------
D---------------------------------------------
A--3-3--3-3--3-3--3-3--3-3--3-----------------
E---------------------------------------------

G---------------------------------------------
D------6------------5-------------------------
A----6-----6------5-----5---------------------
E--4-----4---4--3-----3---3-------------------

Tab by James Beecroft
*