I am converting my garage into an art studio. I want to insulate and sheetrock the walls. There are hundreds of nails coming through from the outside between the wall studs. The nails will prevent the newly inserted insulation from completely filling the space. My house is 66 years old. 15 years ago I had the old siding removed and replaced with vinyl siding. The exterior walls are 1x6 or so, not plywood. Some of the nails are from the new siding, I assume, and some nails are probably from the previous siding that was removed. My question is - can I simply cut off the nail ends (easy with an angle grinder), or should I hammer the nails flat (very time consuming, hard on my arm and neck, hard on the exterior 1 by's). The wall studs are 16" center 2x4 (not 2x6). Because of the thin depth, I want as much r value I can get. I have considered blow-in foam, but cost prohibits this at this time.