First is to mark everything exactly the way it is now.(Str coupler at str box, shift linkage, all wiring, clips, bolts, ect ect. Spray with pb blaster or wd 40, then draw youself a diagram of how everything goes, then get abook on the 56 chev. Some of the illustrations are not exactly right so double check everything. You may have to replace frayed wires, broken bolts so be prepared. When you finally get it out lay everything out exactly the way it came out. Dont get frustrated and be patient.