You might be thinking of the buick 3800 series 2 or 3 motors. Many were supercharged so they are popular for the buggy crowd.
Yeah, the exhaust is and isn't an issue. It looks like they may be relaxing the rules as long as the distance from engine to cat remains the same.
The cool thing about the 3500 and 3700s is that they make more power than a 4.3, now I just need to know what they weigh? Being aluminum they might weigh less than a 4.3. They seem to move those colorados along just fine while getting low 20s mpg, and the colorados are a bit larger and I would assume heavier than a minitruck. They also share the standard newer gm electronics that are so popular with the tuning crowd.
I have no idea if this would be a good swap at this point. I just thought I'd throw this out here and see what other people thought.
Kevo
