In the bottom of a mk3 fuel tank is a retainer ring for the fuel pump. Its bonded to the bottom with some kind of glue. Anybody know that it is?? I'm struggling to get mine to stick now, I've tried some puttys, and Loctite 'All Plastics' glue, but they are not working. The tank itself is polyethylene, and the glue has to be chemical/petrol resistant.