Classic/Antique Car Repair: replace gas engine with diesel?, custom drive shaft, rough guesstimate

Question
I have a 1972 Toyota Hi-Lux with the 80R engine that was converted into a Dolphin 12 foot mini motor home. I want to replace the engine with a cleaner-burning engine using an alternative fuel like biodiesel or natural gas.

Do you know if it's possible to replace the engine (with, say, a Rabbit diesel) and a rough guesstimate of how much something like that would run? Do you have to replace more than the engine and catalyst?

Answer
Jon ;
HI - well if you wanted you can put about any motor into any vech.  but it might cost a bit  and a hell of a lot of labor. I would look in the (jc whitney.com ) catalog as they sell all types of kits for just that. swaps,etc. I would say it can be done , but you will have to have custom ex.system , cooling system, fuel / same tank can be used, drive train with a custom drive shaft. also motor mounts and what ever body work or cutting , sheet metal might be needed.and the suspension might have to be beefed up.  so it could run you into some work.and time, labor.
I would do some looking into it. they have to sell kits for it.   ok >>>