Hy Jim welcome, The 235 will be a drop in if you get a short water pump from one of the vendors. You can use the stock clutch linkage, it worked in hundreds of trucks for years. Rear end upgrades, just exactly what are you looking to do improve top speed, get better brakes, what? Front axle overhaul parts shouldn't be too hard to find, as to front brakes I think 52 and newer use bendix brakes, a self energizing type
