Thanks guys.

Good point about the size, can't really get much movement when it is just a little bigger.

I didn't know that I would have to CLEAN them....gross. That sounds like work, not fun.

For myself and any newbie reading along, I did find a thread on flattening them first to make sure there are no high diamonds. A screwdriver or some other large flat metal object or the sidewalk or a brick. Although it seemed the sidewalk was sort of an "if all else fails" sort of deal.