After letting the mold dry and applying a mother mold with plaster bandages, I was able to remove it and pour my resin blank with Amazing! brand quick-dry casting resin from Hobby Lobby (again, I didn't know about Smooth-On at the time). Much like the silicone, I didn't buy enough resin mix and the mask ended up a bit on the thin side, but I stuck with it anyway. Note that in the pic I've already sharpied in where to cut the jaw, and added a pencil mustache for coolness factor.