The 94 engine will work in your 96. The intake will need to be changed and the passenger side exhaust manifold. The 94 will have EGR and the 96 will not. The intake wil have to come off to pull the engine anyways, so no big deal. R&Ring the engines is pretty simple just take care not to break the crank sensor mounted to the right rear of the engine. I would suggest removing it from the blown 96 engine before pulling it and re-installing the new engine before putting it back on. The manual trans engine and auto each have specific crank sensors that do not interchange. The 3500 is a good trans but if your wanting to do some heavy towing you may want to upgrade to the 4500.