Quite often you don't need to sew up holes at all. Tony Finazzo said he won't even sew up a hole if it a dime size or smaller. I hate to give up all his secrets, but he posted this on a public forum, so he won't be too upset if I revealed some of his secrets. He also uses a piece of fabric softener sheet to seal up larger holes, in conjunction with superglue. I guess he uses them as a patch. I personally sew up most holes for fear of caulk bleeding through. Too often the problem isn't the shot made by the hunter, nor the mouth of the dog, but more likely how aggressive we are on the wire wheel flesher. I will say that most every specimen is mountable, if a few criteria are met. A well plummed, mature, not too badly shot bird is usually salvagable, but isn't always worthy of "flying" mount, but will usually look at least decent as a standing mount.