Ben, Datrus - Gentlemen many thanks for the additional information.
The attached picture shows how one end of the belt is fitted to the buckle. Example shown is a Bavarian.
If you buy the Saxon buckle, be sure to get unconditional return privileges. The "JG" and "GG" buckles are amongst the most heavily faked Imperial buckles and really need to be examined in hand.
I managed today to have a close look at the buckle, the belt holding layout is the same as you show in your post, there was no sign of a maker's mark anywhere. Many buckle collectors comment that the buckles are heavily faked, but no-one has posted a picture of a original - back or front or mentioned what to look out for in fakes! If any member has a picture of a 100% original buckle, please now is the time to post it.