Jerry, if the single-lever dovetail is the same size as the double-lever one then you're in business. Try one of the double-lever mounts on the single lever base and see how they match up; if the fit is snug then simply cut recesses for the 2 new-to-this-old-base levers. If the angles of the dovetails are the same but the heights/depths are different then some judicious trimming or shimming will probably do the trick just fine.
If the angles are different then you're SOL.
I have a Jaeger mount & base that I can send you for comparison of the dovetail sizes but please be advised that the Jaeger locking system is of course different and would almost certainly require machining your base for the Jaeger lock recesses. Not a big deal but it WOULD alter the rifle.
AND, it would be interesting to see how close the various G&H dimensions compare to the Jaeger ones, IOW how about further defining at least some level of interchange if possible?
If you'll PM me your snail addy I'll mail you the Jaeger parts for comparison; AFAIK all the Jaeger dovetails are the same size except maybe some prewar ones.
Regards, Joe
