4" lift question

im buying a 4" lift off of a totaled 89 xj. springs, spacers, leaf packs and shackles. what else do i need to take from the truck to make it work on my 85 xj? will my stock control arms work, do i need to drop the transfer case and get new brake lines? this is my first time putting in a lift and id rather not have any surprises.

Get the control arms; they're almost certainly better than the stock ones anyway. If there's a t-case drop grab it..it will have a different t-case than yours and I don't think they're interchangeable but check around...see if you can grab that too. Brake lines might be usable but don't count on it.