Ive done this a couple of times,,,,,save the engine mounts from the Motor Home,,,they are offset, and move the engine over towards the passenger side an inch and a half,,doesnt seem like much, but it is, because its still very tight in there ( dont drive barefoot, you will burn your foot). Remove everything you can from the front end, and go in from the front. Even with the manifolds off, if you try going in from the side,,its more work than a straight shot in with the trans attatched. And you need a BB 727 to go with it,,,so save the trans too! As far as exhaust,,,the factory manifolds work best, rather than try finding a set of quality hedders,,,I think Hedman is the last for Dodge vans anyway, and dont try Blockhuggers,,,they dump right out at the control arm, and wont work. Get a quality starter, and wrap it with insulation to protect it from the heat, or you wont start right up until you cool it down. Work with the 6's is a good idea,,,,,for now. Good Luck!