I'm chasing a ghost, my poor dad has a really nice, low mileage 97 4wd pickup. A couple of years ago it started having this random problem where it would start bucking and sputtering severely and barely run, like it's choking on itself. Problem was that it was so random that nobody could catch it in the act. Today I believe I finally traced the problem to a failing ECM. Trying to find a replacement unit with the exact matching numbers is providing to be difficult. I know that 1996 and 1997 models are the same setup mostly. I can find ECMs out of like model trucks. Do I need an exact numbers matching unit, or will a computer out of a like truck from 96-97 be able to correctly run the truck?