Difference in between a n°32 mkI and mk II scope

[Hal O'Peridol]

Attachment 32672Canadian REL Mk.1A are marked CGB 78GA.
No OS number.

Mk. II is COS 1650A
Mk. III is COS 2039A
The Mk.1 has nothing other than the name and serial number however there is some irregularity here so I'll dig some out and show the difference.

Is that the one I traded off to you Warren? Looks MUCH nicer now if it is.