I'm gonna be 72 in June, and even in my crippled state, I can get a blanket, pad, old sheet, cardboard, beer, pain pills, etc etc, lay across the engine and reach down to the bell with a 9/16 combo and work those bolts. It might help to "custom make" a couple of wrenches. Look around egag and find some extral long ones, or weld an extension or use a small tube handle. You can bend wrenches with a propane torch.
The more holes in the floor, the more dangerous. More chance for CO (monoxide)/ exhaust leaks, or in case of a fuel leak getting "singed" from fire, whatever. Hey, it has, does, and might happen
