Hi Chuck, I'm going to jump in here, not because I have a lot of first hand knowledge to offer, sometimes playing Devil's Advocate can move a problem a bit faster toward a solution.
You have an engine which would be classified as a good core. Your coach should have enough room and be receptive to an 8V71T.
Like Tom, I don't like wet liner engines...don't care who builds them. Wet liner engines have an "O" ring at the top and bottom of the liner which is surrounded by coolant. Every time a cylinder fires is places tremendous stresses on the liner. It flexes outward pushing the coolant outward as well..but once the internal pressure is removed the coolant smacks back against the outside of the liner. I'd equate it to a bolt of lightning passing through a cloud. That creates a space and the resultant thunder we hear is the displaced air colliding with itself at the speed of light. The pitting of liners, and ultimately fractures causes too many engine failures
A dry liner engine, like the 8V71, has precision fit liners to a solid, cooled block. That is why the 'liner to block' fit is so important. The dry liner can't and won't flex as much as the wet liner because it's backed up with solid cast iron. And if the fit is correct there shouldn't be cooling problems or vertical motion of the liner.
No one asked my opinion but I'm going to offer it anyway. Wet liner engines are cheaper to build than dry liner engines! Front wheel drive cars and trucks are cheaper to build than rear wheel drive vehicles. They sold us a bill of good on that one too!
Can anyone imagine a horse...with front drive? Or a Mule? Or an OX? The animals which provided the power to settle this great land! If they were re-engineered we'd still be back in the Fontier days!
Manufacturers base their decisions on cost of product..not how well it will serve the end user. Look at what we've been stuck with!
I am confident, Chuck, that there is much more valuable information out there with the specifics of bringing your dream to fruition and I will repectfully bow to their superior knowledge on the nitty gritty of you situation.
I'm sure you find the ultimate solution and I hope you share your sucess story with the rest of us.