In the UK, the 4 headlight version had a three cylinder two stroke (TS3) engine. The 2 headlight ones had the 6 cylinder Perkins 6-354. There were a few with a 6 cyl petrol but I never knew of a V-8.
in Aus the 2 stroke Commer had 4 headlights and the air cleaners behind the cab (2 of them ) , but the model with the Perkins in it had only 2 headlights and the air cleaner on top of the motor underneath.Interestingly, the 2 stroke had air mechanical brakes, but the perkins had air hydraulic brakes !
Added by Dmackay on 17 October 2009.