I have a set of unknown brand lake style headers on my coupe and the block off plate gaskets are starting to leak. I can't find anyone who sells them. The block off plate is 5 1/2 inches across, including the mounting flange. Holes are 4 on 3 1/2 x 4 7/8. The tube seems to be 4 inches or just over. Heat wrap makes it tough to tell. Have been to Speedway counter and they don't have them. A muffler guy claims on these flat style plates a bead of red silicon will do it, but there are gaskets in there now and I would like to keep using them. Any ideas on who might have made these? I suspect the were a kit. Any thoughts on the silicon idea or where I can find the gaskets or material to make my own? Posted using the Full Custom H.A.M.B. App!