Thanks Spiros @fiveten, John @johnb, and Rory @rory. How to tackle the front brake discs? I originally planned to use the standard Tamiya mouldings together with their “detail-up” rivets. To do this you have smooth down the moulded rivets, open up the holes slightly, and insert the metal replacements. This went OK, also drilled out the ventilation holes in the discs. I sprayed everything black then used my Nobo chrome pen to represent the actual disc itself. Here’s the result, OK with some cleaning up perhaps, but not really satisfactory.
I had some etched discs which I was keeping for a future project but decided to make a hybrid disc by glueing one etched part to the outsides of the moulded disc. This makes the disc a little too thick but it still fitted in the caliper. I think they look better like this.
As always happy modelling.