Greenie you would have to move to Sacramento for me to do any of that type of work . or pay me a whole hell of alot. I belive the whole head gasket busted when my machine backfired on that day when I tried to start the motor and it filled with water fromt the busted heat exchanger now granted that this is the opposite cylinder from the one that did fill up with water.
Wow, that looks like a lot of work. I have run cast iron Onans for 25 years and with a air ratchet could have the heads off in 5 minutes.
I have 3 Kohlers now so probably someday I will have to do the same.