Refer to thread #1013 titled: 3spd to 4spd swap (no computer necessary). I plan on doing thid to my 91 sedan. Even though some people suggest that I swap in a 5-speed I decided to make it an overdrive tranny. I do a lot of highway driving & want the extra gear for that.
I heard (but don't take my word for it) that the 4spd tranny gives you a little more take off because the gears are slightly shorter. Even if that is not true I still want to do this. I haven't done this yet because my grandma is still using it. Once I get the car then I will do it.
The company that sells it in Miami includes it with the tranny mount. Your C.V. axles will work with it. The name of the company is: All Japanese Engines" 305-685-2550. They will also explain how you can wire the OD switch. The computer in our cars only control the fuel injection. The tranny does not use a computer. If you do the swap let me know how it goes.
GOOD LUCK!