IMHO: Do yourself a favor. Throw the cork gasket as far as you can and use proseal. This has been talked about for years and for the life of me I cannot understand why Vans still sends the gasket. They must have a huge amount of them. Also, use proseal only, for the sending unit and long term you will be glad you did. Sorry for the rant, but so many have had to replace the gaskets later on, what waste of energy! Larry