Thanks mate, I'll check it later, the frame is worn also, so it's a drama. BG (pbu 232)1949-56 garden gate/plunger model 7 with laydown "norton" gear box is 3.46" bottom lug and 3.3" top lug.
Same as big single engine plate spacing ? I would initially guess they are the same, but I have NO expertise with singles.
Believe dolls head shifter is same "norton" gearbox as laydown shifter, again I have NO experience with singles.