If you are going to do an frame swap---------use the frame AND ENGINE< TRANS<REAR< SUSPENSION< ACCESSOIES< WIRING HARNESS

at least all that will be compatable with each other----------then mount the body-------you won't need to do engine mounts, trans, etc,etc---------for a frame vehicle you may have to do a SUV these days as none of the uni bodies will do what you want

Ford expedition has IRS