I have Series III with a C240 Isuzu (as mentioned by Grey Ghost).
A company here made conversion kits for fitting these into Series Land Rovers back in the 70's, it mates to the Series box.
Isuzu C240 powered Series 3
Mine has a high ratio transfer box and is a bit slow off the mark but keeps up with modern traffic.
There are a few cracks in aluminium panels from the vibration !
Colin

