Roy:
Thanks for the analysis. Yep, now is the time to trade the gas engines for diesel and go the safety route. On the other hand, there is something about the feeling you get when a 454 starts up, and it gets even better when the second one goes off! And man, diesel fuel sure stinks! One drop on the deck is like getting a tattoo. It lasts forever. I will probably have to take whatever opportunity presents its self when push comes to shove. Another consideration with diesel is that it will require going to an 1 and 1/2 inch shaft and all the etc. that goes with the increased torqe. All said,it will be fun whatever route I finally get to take. You are also right about the mufflers. I plan to go the fiberglass route because they are much lighter but here again I have heard mixed reviews and opinions. On the present system, there is a fiberglass 90 degree elbow following a short piece of hose coming out of the exchanger (see picture), then later there is an accumulator connector that connects both exhausts and pipes them to the cast iron exhaust that you addressed. I do not know if the fiberglass 90 degree is a good idea or not. Another Commander owner has made the accumulator connector out of stainless which is probably the best, though expensive. I will need some help on this one. Regardless, both engines will come out and the fuel tanks as well. The room needs a good pressure cleaning and painting. I will take the generator out this weekend and have it evaluated. Wish me luck on that! I will start with the drive train this winter and then the electrics. The interior will be next winter's project and the summer will be exterior cleaning and polishing. Whew! Jump in with any advice.
Jerry