I’ve been working on this little SeaKing 5hp 15GG-9015A for several months and she runs great now. Starts on the second pull. The only problem I’m having is the base gasket is leaking. I replaced the powerhead and tried to find a replacement gasket without any luck. So I re-used the old one and used some Permatex #2 to try and fill in the defects. Unfortunately it’s still leaking a little. I have some cork gasket material and could fabricate a new one, but it is only 1/8" thick. The old one is nearly 1/4" thick. I’m unsure if the cork would hold up. Any thoughts on how to proceed?