The brake caliper brackets were iridite coated and the helicoils installed. Had to ask a few buddies about the consequences of using stainless hardware to mount the calipers; I think I suspected they weren’t a good idea due to the chance of galling. Galling is where metal (particularly stainless) gets “smeared” off one fastener and onto the mating part (made worse when that part is stainless, too, like stainless helicoils.) Galling can effectively weld fasteners together before they’re fully tightened, making it impossible to screw them together the rest of the way or get them apart. Anti-seize compound works – sort of – but it’s best to just stay away from the combination altogether. It was good to get that straight before potentially ruining the caliper adaptors that took so long to make. Ordinary steel bolts will be used, and this tip was added to the book.
And yes, the brakes do look small and lost inside those big 17″ wheels, but the Miata Sport brake rotors are a lot heavier and very likely unnecessary – looks aside. If there’s any fade, air will be ducted to them before considering larger rotors.