Too bad I didn't see this idea earlier. My DD drove my DS's car with a very low tire. Evidently, she hit a pot hole, which damaged the side wall of the tire. There was no way to repair the tire, either. My DH left the damaged tire with Sears when he bought the new one.
lol I was explaining these tires to my husband and he laughed and said that his mother had one in her yard for years. He already knew exactly how to cut it and turn it inside out. I guess I had just never noticed it lol.
I have never done this but I have heard you can cut them with a jig saw on a slow speed.............it would be easier and safer than using a knife...(for me at least, I'm prone to cutting myself with knives) Diane