>     I am wondering what my options are as to replacing the original engine
>  in a ('50-'79) bus with a water-cooled engine so I can have some *real*
>  heat...what specific engines will work? And how must the heating system be
>  modified? Any information on this type of modification would be greatly
>  appreciated! 

It would be A LOT easier, and cheaper, I think, to put in a gas heater,
either aftermarket, or original, if you can find one. You can get a
rebuilt one for about $500-$600, and be toasty warm, without going to a
lot of trouble to put in a water-cooled engine.
>     
>      Also- I have never seen a VW camper before. Could someone tell me
>  about what the layout of stuff inside a camper is like? And any other
>  differences between a camper and a regular "bus"?
>  
depending on the year, it will contain various arrangements of folding
beds and cabinets. Some have tops which pop up, and some of those have
extra beds up there. It totally depends on the year...
anyway
all this is of course my opinion.
Richard