My toilet in the basement was rocking and the bolts were rusted. Today I thought I'd pull the toilet and install new bolts and wax, shims, and then caulk. I was surprised to find that the previous owners installed the flange rotated so the fat part of the slot is in-line. They used a closet bolt on one side (it just barely hung on), but on the other side they used a tapcon bolt through the toilet, through the large flange slot, and into the floor. The flange itself is not fastened to the floor. The flange feels pretty solid despite that. It's a 3" sewer pipe and the flange is glued to the OD of the pipe. It sits high so I don't think I should add a repair ring, and I have never tried to drill a PVC flange off. Any ideas? Thank you in advance!!