not installed or tested yet for grx 812 modified with m8000 SGS cage.
16t cannot clear the derailleur tab on a Shimano M591 SGS.
modified for a cheap ospw setup. Deore m510 GS. I have to cut the derailleur tabs to accommodate the pulley wheels. the TT course I race on is straight and not bumpy. so no issues. I think there is room for 17t x2