Here is my process. take the front scale put the blade behind it. Now move it up or down til it looks like where you want it to sit, use calipers and measure the thickness of the blade at that lowest point sticking just above the scales and subtract o.oo1, there is your thickness for the back of the wedge. Next I sand both sides completely flat until it is that size, then on one side I wil move my finger almost towards the middle and press down firmly when sanding to form the wedge, test fit, if thee razor flexes when i close it good, now I sand the wedge outside to fit against the inside of the scales, which isnt much usually, then mock it up and I use sanding sticks to sand the wedge flush with the scales at that point.