Hey Rabbit, if you have a spare 454 laying around and he has a place to change it out, the 600/700 mi trip 1 way might still be worth it.
Motorhomes are a hard sale right now, i've got a 35 ft tag wheels 1986 Alegro, that i can't sell and it has an almost new 454 and turbo 400, good shape for the age clean. I mean i am having trouble getting $6,000.00 for it with 8mpg, and todays gas prices.
Just a thought.
Zip.