Engine oil stop leak products fit into the category of "P.T. Barnum Specials". "There's a sucker born every minute!" They're just a good way to transfer money from your pocket to the seller's. If you don't want to go to the trouble to install a Best Gasket seal, cut a slice of the stainless steel strip that holds the rubber into a windshield wiper blade and tap it into the groove in the block above the upper rope seal.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!