wiring question

When swapping a 7M-GTE into a non turbo you must have the same year harness and ecu that the engine is or the car is? Or does it not matter at all? Also i was wondering what smaller box directly to the passenger side of the ecu is in the dash? do i need to take this smaller box for the swap or will the one in the non turbo dash work?

How many times do I have to repeat this, 87-88, 89, 90-92. Technically there are only two different turbo harness/ECU's, the 87-88 and 89-92 but since 89 was the transitional year you should treat is as it's own, get the harness and ECU from the same car. That smaller box stays in the car, no difference.