http://www.sram.com/_media/techdocs/95-410-762-000%202006%20Pike%20Reba%20RVL%20Dual%20Air%20Service%20Guide.pdf
follow that link mate, its what i used, was a bit of a faff, wish id just forked out the extra £15 and bought u turns.
Basically you need 15w suspension oil
internal circlip pliers
10mm socket spanner and socket to undo top nut (24mm)
5mm allen key
1.release all air.
2.undo air piston footnut, unscrew so the end of the nut is beyond the thread but still half on, use a rubber mallet and give a whack to free the piston. Some oil will come out, drain into something or other.
3.pull out rebound adjuster, undo that side with 5mm allen key. You may lose some oil out here too.
4.remove lowers, i had to give mine quite a yank, they felt as if they were stuck at first.
5.undo top nut of positive air side with 24mm socket, drain oil.
6.use circlip pliers to free the black end of the air piston, then remove air piston.
7.silde all the parts of the air piston off the end of the rod, taking note of order. There is a rubbery bung at the top, just below bottom out spacer, pull this down too, then slide on all travel spacer to desired travel. push everything back on to the air piston in order.
8.re insert piston into left hand leg, push right in, re attach circlip.
9.re install lowers, before putting on footnuts, put in 15mm/cc 15wt oil into each leg, then do up foot nuts to the correct torq settings.
10. turn upright, pour in 3-5ml 15wt oil into top of positive air chamber, do up top cap, re attach all adjusters/caps after pumping up to desired pressure.
Roberts your mothers brother.
Im sure its simple once you know what you are doing, but it was abit longer than a 10 min job for me as id read you could pop the piston out the top of the fork leg without removing the lowers…..i dont think you can, well i couldnt.
Follow that along with the link and you should get it mate.
Hope that helps