BCM education needed

Long story short I searched several terms and nothing popped up so I am posting. I have a 96 and have read the 97 swap thread and doing some thinking with the help of Matt on here. He said any 97 SC pcm will work just needs tuned accordingly. That being said does the vin in the PCM and the BCM have to match on a 96 or does it matter? aka is the pcm basically a standalone setup? Trying to think outside the box here so I can use the hp tuners I have instead of a dhp, as the closest DHP is 2 hrs away and the next closest after that is 3.5 which he will let me use his tuner but takes no responsibility if I brick the computer. I found a 97 regal GS brain that should work and be favorable to me as I have a 97 gs as well so I could have a back up worse comes to worse. The biggest issue I see is that the HPT is based mostly on a vin setup and if going by car vin it will balk but going by computer vin it should allow me to run it ... in theory. ANY help would be greatly appreciated.

I don't think you can use TinyTuner with HPT..... Maybe Turtle or Charlie or somebody can chime in on that. I left the VIN on the 97 PCM because apparently if you change it to the 96 VIN the tuning software can get grumpy, but I haven't tried it and have no reason to. As far as any other VIN issues I have no idea because I haven't bought or used HPT yet.