You may take some material off the Period Correct pad. However, a better alternative is the London Guns pad sold by Mark Beasland. It is thinner and has a curved face. Both grind well. Both will work. You will not get to 5/8" as the center hole in the Galazan pad will cause you problems. You are able to rou d the edges and there are many past posts on this forum about antiquing the pad.

Dennis Earl Smith/Benefactor Life NRA, ACGG Professional member