In your situation I don't know. On these older cars mileage stays in the cluster. On my 99 bmw dash mileage had to match the pcm or the dash threw an errorInteresting conversation here as I'm thinking of going down the PCM swapping path too with my '14 GT. I'm not very knowledgeable about this sort of thing and wondering if there are other things that may be affected by swapping back and forth, mileage recording for example?
Also having difficulty finding the right number: DR3A-12A650-ACE