Cut new cardboard insert to fit between windscreen support and canopy hoop. Refit canopy to fuselage and checked fit. Called Van's Builder Support and discussed canopy fit and Big Cut. Removed canopy and sanded notches in bottom edge of canopy with Dremel sanding barrel to provide clearance around vertical tubing on skirt area of canopy frame. Refit canopy to fuselage and checked fit again; small amount of additional sanding required.