I use a "popper offer" that I got from a pal of mine that has a tire center. Basically it is a piece of round stock aluminum 3/4 inch diameter about 18 inches long with a flat edge bent back in a half moon shape similar to a pry bar.
Slide the thin edge under the cap and pry by pushing down on the handle and the cap pops off.
Simple to make and simple to use without doing any damage to the cap or wheel.
Hobert
