My outdrive is very old and many replacement parts are N.L.A. My problem stems from having to replace the gear houseing to drive houseing gasket. The gasket is no longer made. I thought that if I hade to make a gasket, I would do so by placing gasket material on the houseing and gently tapping the edges with a ball peen hammer. Is this the correct proceedure? Also, if it is, should I use cork or some other material? It was also suggested by an acquaintece, not to bother, making the gasket,just use Permatex. Has anyone any experience in this area? Thank you.