Clearance between caliper and rims

Hi, following Martyn Matchless path , I am fitting a BMW K100 triple trees (yokes in uk!) with Yamaha R6 forks to a Commando frame, easy job, just some milling the holes from 41.7mm to 43mm, found the right taper rolling bearing , put some spacers here and there, a Honda CB 750 front hub laced to a 18" alloy rim, a Honda fireblade 900 rr rotor.......done . Now ,I will fit a Grimeca (same as Lockheed) caliper , but need to adjust the spacers between rotor and hub to clear the fork sliders, nearly done ...but the last step is to space the caliper away from the spokes , what are from your thoughts the minimum clearance, is 2/3 mm a safe gap ??

Any clearance should be enough if spokes proper tension as unbraced forks will twist before wheel deforms sidesways a silly mm. You could also tweak spoke tension to slightly off center wheel w/o any notice hands off. Tire wear has more influence than a silly mm out of line tire patch. Moving tire slightly away from rotor will help balance out the mass of brake causing gravity to pull forks to that side which infulences hands off drift.