Here's what I do...
- Use the tang of the knife as the drill template, match drill the fastener (or pin) holes.
- Transfer the profile outline to the back sides of the slabs. Grind to the outline. It takes about 5 times to grind, check against the tang, remove from the knife, grind a little more, check again, take off, grind, check, until the fit is perfectly flush all around the profile.
-Grind the contour shapes.
-Sand,
-Sand some more
-Finish sand.
-If the scales are removable, then I apply oil.
-Install.
-If the scales will be epoxied, I only finish sand all around the profile, then epoxy in place.
-Cut and grind the pins flush.
-Finish sand the contours and polish the pins.
-Apply oil.
Hope this helps. The above is the very distilled down version of the process, but if you are at all inclined as a craftsman, you can figure out the details.