Yes, I did some research in the numbers, but nothing conclusive, SS cars certainly used the same plates on their Jaguar bodies, so it was an SS fitment, have pictures of 3 originals fitted to the Big 4 bodies.
There is no column in the factory ledgers for sidecar chassis numbers and they are shown neither in the case of the RAF Model G 16H outfits, nor the SWD Big 4.....It would seem that they were simply a 'shop' number that allowed them to be followed through the production process (which was probably on a piece-work basis so records needed to be kept of who made what)or to ensure that particular parts were mated up again after processes.
The BSA ledgers show tally numbers which I assume is what you mean by Shop numbers, so is that a possible theory for the second number on the chassis?
In the case of a military combination the sidecar body would presumably be the last thing to be fitted in the factory and would cover up the number on the spring hanger.
In the case of a civilian sidecar supplied by Norton in peacetime the majority would probably leave the factory to be fitted by a retailer so it would need a unique number for the guarantee?
Indeed Ron it's all really fascinating then hopefully I'll be able to pass it all onto them and they can pass it onto the next generation :) Hope you are all keeping well in these crazy times.
