I have tons of decoys but all floaters. Your idea on cutting out for the keel would work except the ground is frozen and we are hunting stubble fields where the decoys would not be very visable setting flat down on the ground. Guess I will have to work on a bracket or support of some type to get them up off the ground a bit so they can be seen better. Last weekend we used some old decoys without a keel but the ducks would not commit. I'm not sure they could see them.