the 2 and 4wd truck pans should fit but you may have to modify them a little depending on where you put the mounts on the frame, the motor is a bit shorter so you can shift it forward a little when you weld the new mount supports in to avoid messing with the firewall. the transmission in your motorhome will not bolt to or stand up to your turbo engine. on the rear axle if it has the full floating axles it should be strong enough to handle the engine. if its a fake dually rear axle its the same as a stock truck one, may or may not take the extra power. you will probably have to have a custom driveshaft made. do you really need a turbo motorhome, a non turbo should have plenty enough power over a L20b engine and a lot less hastle if something breaks while your on vacation