Worth doing, Norton clutch came with the gearbox -bought a Commando belt clutch basket, front pulley, which was mated to part of the ESA sliding onto the crank spline, E10 belt, nut and split pin for safety... the final drive chain and sprocket set up aligns well, Commando 18T gearbox sprocket, 48T Vincent rear -only issue is the chain, a 530 needed for the front sprocket if using a Commando one, it gives some lateral movement on the narrower rear 48T Vincent sprocket, which I've assumed is for a 520, seems to work fine. Started with 108 links 18T/48T as per flash spec (Could possibly get a 19T front or even 20T?). Reduced chain length to 106 links to maintain nimble wheelbase.