go to any auto parts store and get the v8 motor mounts they should bolt right in. the tranny crossmember go to a junkyard for that any one from a g body should fit. youll need a new tranny mount too the driveshaft yes have one made or junkyard one and replace the ujoints. if you dont know what a g body is heres a list
http://en.wikipedia.org/wiki/GM_G_platform_(RWD)