I have a new Caspian frame and slide that I am trying to fit. Is it unusual to have to remove a few thousandths off the very bottom of the slide? The grove cut in the frame is .114" tall and the slide is about .117".
WHen fitting a Caspian frame and slide I usually have to remove material off the bottom of the slide, the top of the frame and the sides of the rails on the frame. I remove all material with a milling machine and a new carbide bit running fast. Doing this with a stone is doable but you might want to use a fine file until you get close (.001). Get a good set of calipers to see how far you need to go.
Z1500, I know what your going through. I just finished mating a Les Baer slide to a Para frame. Those slides are hardend and my files were almost skipping off the slide. I went slow and it came out nice.