All you guys who recommended Chuck were SO right!
He showed up on time and he and son C.J. are hard at work on my drives right now. Chuck showed me that my bellows are actually in pretty good shape and don't need to be replaced for awhile. What he did find (and he showed me every component):
Starboard drive - The exhaust tube was a little deformed at the transom end, which probably contributed to the exhaust noise. Gimbal bearing is shot, not because the bellow is bad but because a 'sealing ring' wasn't seated properly and allowed some water seepage. U joint is okay.
Port Drive - no issues found.
So, they're replacing the gimbal bearing and exhaust tube as we speak, and servicing the water pumps. Chuck found a transom housing bolt that needs to be replaced, so they're gonna do that. They're cleaning everything up as they go and will complete the job today.
I'll tell you honestly that he could've banged me for a bunch more money and parts without me being any the wiser. IMO, these are some genuinely nice, honest guys who know their s**t. I'm very pleased.
Thank you all!