Just tossing this out there.. I have only a slight knowledge of the actual mechanics of cars. Is it possible that the car got its wire harness from japan and its just different than a US one? Do you know if the 1991 engine was actually a swap from the original? those would be my 2 guesses at it. I would have thought they where
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interchangeable
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.. Is this 87 7MGTE from japan?