Well, there was little clearance to play with there!
I had some 1.2mm washers and tried them yesterday = the rotor bolts fouled the inside of the fork 🤔
3 x packets of different thickness Hope shim washers just arrived from ChainReaction. The 0.8mm
just means the domed bolt heads don't foul the forks and the spokes are ~1.5mm away from the caliper.
There is another packet of 0.25mm shim washers, but they come in packets of 10, so not enough to double up to 0.5mm - which would probably give equal-ish clearances. I'll order anther packet methinks.
I'm surprised at how tight these tolerances can be - admittedly between different manufacturers' components. Google suggests spokes hitting calipers is far from rare and probably asking for it if using large-ish flanged dyno hubs?
Heigh-ho fingers crossed all will now be well in Slope's new modern thru axle, carbon forked, disc braked biycle world with all
black components
Many thanks for your advices and inputs