righto, i have a mk3 bootlid withe the number plate reces welded so i have about 5-10mm to fill and its done apart from a bit on the right side were dopy me sanded a bit to much and it needs one more tiny layer now, doh!!but the wiper blade and boot lock hole are a night mare, i have fiberglasd behind it (it was to hard to weld in that tiny space!) but every time i put a bit of filler over the top i sand it down it feels smooth as a **** bit on closer inspection there are two or three tiny lil holes were filler has had a buble in it or somthing, how do i do this with out the bubles!!! pls help me