adding rear disc breaks

I have a 94 xj with Mopar rear axel an drum breaks. I came across a 97 grand cherokee with mopar rear axel an disc brakes, How much trouble is it to put the discs on the 94 axel an will my proportioning valve work?
I'm gonna do it but I thought maybe somone has done it an could give me a outline an save me a few problems

do the search for ZJ rear disc

it's been covered quite comprehensively.

Fairly simple. Can all be done with tools around the house and a few new bolts.

Very easy swap. There are a bunch of threads on it, here's mine:

BRAKE SWAP.