So... it turns out that the caliper mounts dont quite work for the FZR250 front brakes. Doesnt miss out by much, about 5mm on the OD and probably another 5mm width wise.. so Plan B is to use the SRX600 front and rear wheels... They are 18" so a little more difficult to get tyres but there are Pirellis out there that are not too bad. The original SRX250 had an 18" rear but was only a 100/90-18, so only 12mm difference in rolling diameter still leaves plenty of clearance. I am able to get a rear sprocket that works to get me almost identical gearing and I will just need to sort out the rear brake mount... either weld a mount onto the swing arm for the torque rod or have an adapter made for the 3WP caliper mount. I suppose that this way the bike will then be all SRX rather than an SRX FZR hybrid...lol. Looking at that it might have been more like 10mm out in diameter... Front guard would have needed to be lowered as well I think.