If you were to mask a 1/16" above and below the paint edge on the filler neck and swipe a thin amount of JB Weld over the paint line and then immediately remove the tape before it dries, you will have a permanent seal. The fumes will never get under that edge. I've done that many, many times with great success.
Thanks for the suggestion, I did this and it was pretty basic. I'm looking at it as cheap insurance that I hope I'll never need.
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So, once the JB Weld was thoroughly dry, I replaced the gas cap and lock, ran the fuel lines, installed the tank and seat.
After a few bumps to the starter, she roared to life! I could not resist to take her for the first ride since I bought it, about 3 years ago! She did not run great but was able to take me around the block. There is nothing that can make you happier that a running engine after a rebuild.
I bought these carbs from BranDen, they are set up for a stock bike, so obviously I need to do some jetting now. Here is how she sits...
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About this time, I was interrupted with a delivery to my house....
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I helped my buddy buy this '68 Corvette for the classic car collection he is putting together. He is out of town so I was more that willing to accept delivery and give it multiple test rides! It runs fantastic, needs no jetting so it was a no-brainer on which one to take out!!