I have a 203 rotor on the front of my 29er , the fork is reba post mount
usually the appropriate adaptor is SM-MA=F203 s/p, which I installed
brakes never really worked well, recently I pulled the pads and noticed the top 1/16" was not wearing down on both pads, so the caliper was 1/16" too low, yet everything is shimano and under spec???
I started digging through my adaptor collection and found a SM-RT75-DH
looks exactly the same except the part that attaches to the fork is 1/16" thinner

I've done some searching and when you search SM-RT75-DH only rotors come up, which is what rotors I have. But Cant find anything about the adaptor. seems kind of weird since the rotors are pretty common
Shimano lists the rotors as compatible with Saint
and that they are non series
are they part of a combo package?