RE: fuel tank removal/replacement
As far as removing the lag bolts, we were removing the rear fuel tanks out of my neighbors boat and ran into the same problem with the hold down bolts.* A fireman friend brought down a set of Sears Craftman bolt/nut removers and zipped them right out.**I don't know their official name, but they come in a kit with different sizes and look like sockets, they*have a spiral thread inside.* As you turn the ratchet they bite into the metal of the bolthead/nut*and it either turns the bolt out or breaks it off.* We broke one off flush with the stringer, but the rest came right out.
I don't know man, fuel tanks have to stay in there a lot of years and I don't know what your total fuel is.* But I wouldn't want to give up too much range.* Knowing the distance you say you run for fishing*and with those 3208's in there???* I would think you would want a couple*hundred gallons on board.* If I had to take the exhaust off, I think I would do it.* JMHO