B31 rigid 1949 gearbox adjuster

[Yamtx750]

Hello
H
I have taken over the restoration of my dad's 1949 b31 and need some advice on the gearbox adjuster for the primary chain. I had to replace clutch parts that were not tightened fully when it was first assembled and on trying to move the gearbox forward to remind the primary chain the adjuster does not move anything.  The lock nuts for the adjuster are also on the opposite side to the manuals description of their location.  Is there any way of changing round the adjuster lock nuts and bolts on the gearbox without removing the engine form the frame? Sorry  I do not know these bikes very well I confess to being a 1970's Yamaha man normally

[Dean Southall]

You don't need to take the whole engine out. You should get access by removing the prmary drive and rear chaincase. A bit of a drag I'm afraid. Do you really need to turn them round?