Injector size changed in 94. I still think I'm right though. I think the only thing that would be different that the EEC would care about would be the EGR, and I don't know if its an issue for you or not.
Just reuse your 89 engine harness and use your 89 computer. It will run fine on the 93 engine. You can use the motor mount from either year, just don't mix them.
Otherwise you will need do alot of rewiring to use the 93 EEC, cruise,dis...
I don't think that they made an SC that didn't have DIS. And my 89 has more options than my 90 or 93. I don't think he has to change either, but I also don't think that you have to rewire anything.