I used a KD 3535 gasket and 1.5mm mcpcb and this is the difference I get from a factory RRT-01 which the TCR-1 is the same.
If you belt sand the mcpcb down to 1mm you shouldn’t have a problem fitting the factory gasket. As you have mathematically figured out there’s not a lot of difference, and anything you do to lose a little height gets that bezel screwed down further. Using the thiner KD gasket and a 1.5mm mcpcb always worked out for complete coverage of the bezel O-ring with the KD replacement reflector, so I never tried anything else.
to same parts work to replace the stock mcpcb, reflector, and centering ring…
on TCR-1, 2012 RRT-01, and Eye10 Rotaries…
lights that came w xm-l, and are being switched to 219b
I also swapped the lens to 1mm sapphire, eliminating the bezel gap almost completely… (stock lens is 1.5mm)