swapping different year pcm's..
 

i'm looking at buying a used chevy or gmc truck and would like to use the 2002 truck pcm and 6.0 liter out of my 86 cutlass. what all would be involved in doing this(swapping pcm's)? does the vin number need changed in my current computer to match the truck i buy? my hp tuner license is for the 2002 pcm as well so that would save me a couple of bucks as well. thanks guys.