If you've got the original ones like I had, I just sprayed the "dished" area full of brake cleaner to soften the glue holding the "plate"... Let it sit for a few minutes, then used a small flat head screwdriver to start prying it up and peeled it out.
The place I had cut them out for me is WaterJet solutions, in Central Point, OR. The number is 541-665-5880