Are they the same calipers are granadas/scorpios/sierras have on the back? (and the same as in the conversion on the S1 on that site?)

The hubs are the same, the drums seperate from them.

When i did mine i used washers to space the carrier over the disc centrally.

Do you have rear apportioning valves or fixed rate ones? I run fixed rate, and so do a lot of others, alleged to be the best way to run it.

That site is pretty good i don't think there is much better to be honest

Any questions i'm sure i can help you