Hey Space Moose! its four chords. but two shapes one is an old swing Dom7 power chord grip and the other is the "Stairway to Heaven" intro chord grip you are probably familiar with. Here is a quick tab. just tinker with it tell it sounds the way you want it to! Good luck hope this helps!

---------- 5-------9-----repeat then this is the change 3--------7----------------------------------
---------- 8-------9------------------------------------------- 6--------7----------------------------------
---------- 6-------9------------------------------------------- 4--------7----------------------------------
---------- 7------11-------------------------------------------5--------9-----------------------------------
---------- x--------x------------------------------------------- x -------x------------------------------------
---------- x--------x -------------------------------------------x------- x------------------------------------
The last two should be looked at like chords the tab got a little greasy toward the end somehow.