Thanks for the detailed response.
Well you guys have a lot more regulations to deal with in the UK than we have in the USA… At least, currently…
I wonder if you might have a moment when you get your wheel off to measure the diameter of the axles on your RS and compare those to the I.D. of the bearings on the GEN one wheels? Hopefully those are the same/perfect Match.
the next question is the build casting/shape /offset of the rear wheels and exact positioning of the bolt holes for rotor and sprocket , the Cush drive inserts, etc. My concern would be having the chain path not be able to run straight regardless of which spacers one might use.
With a good set of comprehensive measurements, this will be easy-ish.