Ron (Netherlands)
Well-known
Looking at some of these conversions, it would appear the lug the base plate hooks onto has been upgraded to the larger size. Mine still has the smaller original lug (and vulcanite). I guess they replaced the whole shell and baseplate on some conversions?
I think the upgrade to a bigger shell and baseplate was done after WWII when the regular LTM cameras (the IIf and IIIf) had these bigger bodies. Probably yours is likely a pre WWII conversion: does it have a flash connector?
Btw pre-war conversions sometimes got a flash connector, but no synchronization since that was only introduced with the IIf and IIIf?