Just as a reminder, those cheaper units at the parts store need to be modified if using a manual brake push rod (the ones under 1"). They don't have the slot for the retainer, and without the slot, the push rod can fall out and leave you without brakes. If you don't have the tools or know how to modify, like me, it is just easier to but the one that already has it done. If you do have that ability, then disregard.

As mentioned, call Dr Diff, he carries a couple different sizes and will help you decide. I have manual disc brakes so I went with 15/16", even with the 92 Viper front calipers. Also have 10.7 disc rear kit from the Doc.