+1 to the suggestion to swap the sheet metal to a more modern chassis. A complete older motorhome can be bought dirt cheap, as the coach has a tendency to fall apart long before the running gear wears out, and old motorhomes can be acquired for scrap iron prices pretty frequently. A chassis from the 1980s or early 90's will be narrow enough for the track width to be pretty close to correct. You'll need to do a little modifying to put the steering column in the right location for a conventional cab setup, but a modern chassis and suspension, plus an automatic transmission will already be in place. I've got a 454 engine Class C motorhome on a 1 ton chassis sitting behind my barn, and another one with a Ford 460. Both of them were able to keep up with interstate traffic without any kind of final drive gearing change, also.

Edit: The old school way to get the "lowered" look you want is to "channel" the body. Raise the floorboard to drop the overall height of the sheet metal on the frame instead of doing massive suspension mods that will destroy the original geometry and make the thing a rolling deathtrap in anything but a low speed straight line. The laws of physics are not "suggestions" where handling is concerned, and you can really benefit by utilizing a major manufacturer's research and development of a chassis that was engineered to handle right from the factory, no matter what kind of sheet metal it happens to have grafted onto it.
Jerry

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