If you want to get rid of the c clips then this is the way to go. Do it now and it will cost a lot less than trying to do it later. If you want to keep the c clips then use the ends that are on the housing right now. Cut the right side farther in than the left and you will have the extra 7/8 stock that you need.
If you are going to use disc brakes then tell Moser up front and they will send you the flush mount housing ends. That way you will not have to do any machine work to the caliper brackets.