Toilet bowl shims
I have a toilet flange (in concrete slab) that is set too high and the bowl rocks. I have used the plastic shims to level the bowl and it works for a while, but over time the shims move and the bowl rocks again. An old timer I know says he used to buy a toilet gasket (rubber or neoprene) that was bigger thyan the toilet base, had a precut hole for the flange and was 1/4 to 3/8 inch thick. He would set the toilet on the gasket, bolt it down and trim arounfdthe bowl base with a razor knife.
Anyone ever hear of this? Are they still made? Where can I buy one?