There's also some re-pinning of the harness that needs to be done, too. I'm not sure what all it entails, honestly. Typically it's been the 94-95 guys converting to the A9x EEC, not the other way around. The 94-95 cars use a CCRM, which controls the AC, fan, fuel pump, and transmission if it's an AODE car. How much of that stuff would need a rewire vs. a repinning I really can't say without looking over a wiring diagram for the engine harness. All of this is assuming you're using the 86 harness though. If you use the 94-95 harness, I'm not sure what will swap over and what won't. You might be better off selling the free stuff and going with an A9x conversion.