Reverse wiring?

[Darkapollo]

Ok, after a very disappointing day at the track, I have decided I need to upgrade my computer.
HOWEVER since 90/91 cars are a PITA to burn cals for (my burner doesnt work on 87c256 chips) I have decided that I should reverse swap the engine harness back to an 89 (since i can burn chips for those)
How hard is it going to be, and is it even possible to keep some of the goodies (like my rounded dash and electronic speedo)

[JDAWG]

dana i thought shelgame did the 90 cals now. But anyways i have seen people turbo 90 and 91 cars with the 89 harness so it can be done. Look at the sticky at the top of the page and compare your 90 bulkhead to an 89 harness and just move your pins.

[Darkapollo]

he does.. its just I have plenty of 27C256 chips sitting around and the stupid 90 needs a different series (m87c256)