Les, I cut mine from the top. I am not sure about the markings, but I cut them as I took them out, so I knew where the top was. LOL I cut 1 full round out of each, and it was perfect. A drill will not work. Trust me I tried an electric drill with a cutting wheel. I just went out and bought me an angle grinder, and it went through them like butter.

You can see by the pic in my signature, the stance after cutting 1 round.