Hello all, I am reinstalling a CASE wall toilet and need to buy a new gasket seal between the toilet and the carrier bracket. I’ve seen a lot of information for the 3000 model but looks like mine is different. It is a two piece toilet (separate tank and bowl) and has 2580 on the underside of the tank lid. The carrier bracket has a 4 inch diameter hole that is 1/2 inch deep where the seal seats. The carrier drains into a 3 inch copper pipe. I was looking at the Zurn neoprene gasket but it is 5 plus inches in diameter. Seems too big to me. The house was build in 1968. I’ve included some pictures. Appreciate your time and help. Thanks.