Lukey,
I don't know what that top yoke is but it is not A10.
The instruments are Norton Commando.
The engine number seems to be 1954 Road Rocket but the RRs delivered here had RR in the engine number, the single R being on Super Rockets.
The frame is early 1960.
Not sure what you mean about the speedo mount and RGS.
Trev.