Magnum and Wiring Swap

So, what is actually "needed" out of the donor harness to make the Magnum run? I would imagine it's a little different between obd 1 and obd 2? Following along, thanks for the info!!
I did mine with a stock obd2 harness and PDC, it was fairly easy with a factory service manual. If you want really simple, joint the magnum swap group on Facebook, the Moderator makes swap harnesses for od1 and 2 and they are just the necessities.
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