Welcome to the Forum.......The Mark II rubber grips will fit the later, ,A-100 frames, BUT being there is a cutout on the left side of the rubber or ANY Mark II grips,when you try to use them on a Mark I (or standard auto) you have to put some sort of "filler" ?? in this cutout for the hold open lever, OR the pins in the frame will work their way out, to the left, into this "void" and will lock up your gun,, when the sear slips off inside the action,,,,,,,,so pay heed.......................
try not to use anything "permanent" as you may need to put them BACK on a Mark II someday :roll: