I think you will find the coon a lot easier than the fox, so practice on that one first. Fox skin is a lot more delicate. I used to put a loop on the end of a straightened out coat hanger (a little electrical tape over the sharp parts) and use it to push up beside the bone to break up the connecting tissue a bit. Made it easier to skin. Never did a frozen one though - hopefully it will still be supple enough to skin out like a fresh one. Stay close to the bone!
