Mother of pearl works well with metal working tools. A file, emery cloth, wet or dry paper, bench grinder, drill, etc. It works about as fast as aluminum but is brittle, frangible and can raise fine dust. For fitting K grips to the DA frame, the locating pin hole has to be moved. I do that first and then work the excess down to fit the grip frame. The top of the grip fits well with little work.

To locate the hole, I first punch out the pin from the frame and use the hole in the frame to start drilling the new MOP hole. If you mislocate the hole a little, just enlarge it enuf to get external fit and fill the enlarged part of the hole with epoxy glue. Wax the frame & pin, put the grip in place till the glue sets.

For reaming the cylinder to take .44 Special, I carefully turned a piece of drill rod to a close slip fit into the cyl bore, with a shoulder on it to control depth. I filed random spaced teeth around the end and hardened it. I turned it by hand to cut the new depth. I was pleased that it takes a very close inspection to see evidence of it. Without knowing, it wouldn't be seen.