Best way that works for me is lay the liner on the handle material, with the bolster on if it has em and clamp it in place. Drill the holes for the screws/pins and scribe around the frame. Take the g10 off the liner and drill the holes out to the finished size and counter sink or counter bore them if you're going to and then cut the g10 down as close to the line as you can without hitting it. Then attach the scales to the liner and sand it to final size. The reason I take them close to finished size before attaching them to the liners is the less material to take off usually means less heat generated. Once you have the scales shaped and to the final size, remove them and round off the top of the edges and buff them if you want to.