Ok, so I had my transmission rebuilt by a friend of a friend it was a learning experience. I put it back and it requires a lot of gas to make the truck move like it is slipping really badly. To me it seems like the clutch packs don't engage properly and doesn't shift right. So, until I can figure something out on that, I purchased a used an '93 4l80e to put into my '96 Silverado 2500. I need to know what is required to make it work or if it is even possible. The biggest problem that I can see is that the '93 doesn't have the black box (not sure of its name) on the side of it like my '96 and I'm not sure how to go about getting past it. Any advice would be greatly appreciated.