Isn't the 3/4 ton driveline enclosed for part way back, and then open the rest of the way to the rear axle? If so, you should be good to go although you will probably have to have the length of your drive shaft modified or simply get a new drive shaft. You will probably have to go with a short shaft water pump also. The short shaft water pump solution is less than ideal as it puts the fan down lower than it was resulting in cooling that is not as good at low speeds. Somebody makes a kit that puts the water pump back where it belongs when doing the 216/235 swap, or you could just go to an electric fan. I'm using the short shaft pump in my '37 truck with a 235. It works ok, I just have to keep my eye on the temp gauge at low speeds and idling.