That would have been a Brilliant Conversion!
Shame your brother didn't appreciate it. Must have taken some doing to get that configuration Motor in there!
Actually it was very simple. Bought a kit from one of the used engine importers, where I sourced the engine. Came with engine mount adapters to fit the Kombi crossbar, new bell housing to suit kombi gearbox and Toy motor. Used a radiator and piping from a newer (T3?) Kombi and made up a bull bar/radiator mount up front. VW never brought out any of the old busses in a diesel version in S. Africa, the first were the new shape (T4?). They did however have a T3 with an Audi 5 cyl engine, one of which I owned at the time of parting with my old bus. Now this was an awesome Kombi, albeit rather heavy on fuel at 15Lt/100Km