Car Forum World

I have a 1990 rx7 convertible and the engine is in need of a rebuild. I'm considering really replacing the engine with a 13bt since it could probably cost the same for the engine as the rebuild itself since i',d have to pay for labor and all that fun stuff. just, I heard I',d need a new driveshaft, but do I also need a new tranny, rear end, ecu, or anything else to get it running well? Or do you have any ideas as to something that could be better for me? or am I way off in considering this?