A topic that causes more speculation than anything else that I can think of. All except the first two prototype BSA RGS frames were stamped GA10. All other A10 frames were stamped A7. Some of the obvious differences were: All four front engine mounts were castings, but beware! this is not an infalable indicator of an RGS frame. There are some A10s about fitted with four cast lugs. The headstock wrap round reinforcment plate is different to the A10. There is no provision for attaching a tyre inflator to the RGS frame. These lugs were not fitted to the RGS, but they were fitted to A10's. The top fork yoke has no provision for a steering lock either. It should not be forgotten either that the RGS started life as a built to order custom bike made by Eddie Dowe of Banbury. Some of the parts that Dowe needed to build his Rocket Gold Stars were not available from BSA as spare parts. The story goes that Alistair Cave supplied the relevant Goldie parts surreptitiously. There are many Rocket Gold Stars around that are not replicas fitted with non original items like non QD headlamps. All UK bikes were supplied with those. That said, customers could choose from many different options when placing their order ranging from roadsters with standard front footrests to full clubmans trim with an ally tank. I would not be to worried by a what self appointed know all says. You are not trying to pass it off as the genuine article. Just enjoy your bike for what it is. For what it is worth, I think that much of the hype about what is, or is not real, is fuelled by people who regard the RGS not as a motorcycle, but as an investment.
John