Hi
Dont know if the speedo is magnetic or a chronometric unit so this may be irrelevant , but there is a chap at quite a few shows who sells replacement bodies, bezels annd glasses etc for both magnetic and chronometric speedos, the magnetic speedo and rev counter bodies are to take his screw on bezels, like a chronometric rather than the crimp on type which is a pain in the backside to assemble neatly even if you use a new bezel. If you are using a digital unit rrather than an original then could you fit it in one of these rather than using an original and removing the guts
Unfortunately all my paperwork is still in a box somewhere, possibly in Ireland so dont have the guys name to hand but hes at a lot of shows and the speedo parts are all he does,maybe someone else will be able to supply his contact details
Paul