Serial # Question

[David_Hayward (RIP)]

Brian, I have a BIG database and it it gets bigger and better the more information I have. When I have nothing to do, which is never it seems these days, I work through a big pile of old UK civilian regos., and they yield up more numbers from demobbed trucks.

I have often wondered what the prefixes were before 'R' [rhd] on CMP Chevrolet engines meant. I suspect it is to indicate improvements but do Service News advise?


D