Brake swap problem

Swapped a dual diaphragm and master cylinder out of a 95 XJ into my 87 XJ. The idle raises up a couple hundred rpm's when I put my foot on the brakes. Also It feels pretty much like manual brakes. My guess is the booster is shot. Is there anything special I need to do to make this work? Any help is appreciated.

LBJ-

I will be doing this conversion shortly myself, and I would suggest checking the power booster check valve before you think the booster itself is faulty-let me know what develops.....do you have a service manual? Thanks, and good luck

BN6339

The brake booster was definately shot. The master cylinder was leaking into the booster so the master will be getting replaced also.