i have a 03 mercruiser 5.0 mpi with bravo outdrive standard cooling that i just rebuilt and dont have a ecm. it says i need ecm 864376t05, im looking for a used ecm, ive found a bunch of 5.0mpi ecms on ebay, my question is what is different about all the ecms, why wont any 5.0 ecm work with my...
