hi all I have a Mark iii speedy ref 176.002 anyone know how I can clean the crystal ?

 

I believe those are sapphire, and can really only be polished with diamond paste and (preferably) a Dremel-like tool. If it's really scratched up, it might be better to just have it replaced.

 

The watch was made circa 1973 I didn't think they had sapphire back then ?

 

Its a mineral crystal not a sapphire. you will have to get it replaced.
https://omegaforums.net/threads/polishing-mineral-glass-mark-ii-anyone-ever-succeed.40476/