Yes, it's a perfect fit with the same screws as the Navy frame. Front triggerguard screw has smaller head on both. Called them my Thunderer-Mason Conversions
. I've shot the guns with those grips many times, but have them back to the Navy grip again.
Interestingly, when I tried to put the Navy grip frame on the Thunderer that had loaned it's grips to the R-M, it all bolted up okay except the slot for the trigger wasn't long enough in the back so the trigger wouldn't fit. It could have been filed further back but I was just checking the fit so I left it alone.