I have just got back from the engine rebuilders workshop because i want to get my block chemically cleaned, honed and resurfaced and he for some reason needs to see my timing case cover because he says they came out in two versions?

he said one sides flush with the surface of the block and kind of uses the same gasket for the top?

can anyone tell me if there is a way to distinguish the difference as i wont have access to my timing case cover until next week..

motor is a series 1 au, but he said that does not tell him which one it is...

If they are going to surface the block, it will be done with the timing cover bolted to the front of the block