The 4 speed hydros typically used a common main case & the front casting was like an adapter to mate it to a whatever engine & also they used a variety of output shafts & extension housings. These same trans. were used with a wide variety of motors. Ford put them in their Lincolns. Kaiser, Nash, & Hudson along with other builders such as mail trucks. Military tanks used two, one on ea. engine. A busy trans. shop would keep a few main boxes built up & put on the front or rear part as required to give a customer a 1-day exchange. That being said, I've never converted a truck but I feel sure if you compare the back of your block with another, you'll find them the same. Doug
