[THEFERMANATOR]

I know you need to be careful swapping powerheads on some of these engines as tuners and adapters were changed from year to year as well as tuners. The 88 150 is actually the equivelant of an 82 175 in most respects to port timing and such. Go ask the MERCURY guys about following the idea that just because it will bolt on it will work, many a MERC has been fried that way. I'm not saying it isn't possible, but you have to check alot of variables when doing it. Also in 88 most of the cross-flow V-6's had gone to large bore engines whereas in 82 they were all small bore for the most part. Many times they would make a slight change in the cooling jackets or something and it would cause overheating if you didn't have the matching deflectors in the mid. Also the carbs changed in 83-84, as well as the heads were opened around that time for unleaded gasoline with lower octane ratings(this is why OMC offered the low compression heads as an accesory if you didn't want to run 89 octane). Also you have to pay close attention to the exhaust portion as it goes through the midsection adapter, I know they changed them some time in the early 80's to a different design and you had to do some JB welding to avoid overheating if you swapped to a newer mode powerheadl or vise versa.