Can't disagree with the king, who helped me many times with my carbs in the past.
However, I always enjoy and learn the most from safe experimentation and found this fuel resistant 2 part epoxy sealer that has worked for me for many years:
I have used Loctite Weld compound from the parts store with excellent results on both my Carter W-1s sealing the worn input threads. See my 235 link.
It's my daily driver and the seals hold up nicely at 200* and hours of freeway driving.
On this 235 I also use compression fittings, rather than flared, which would be arguably better, as in safer.
Also used the same Loctite Weld many years ago to patch a small hole on a gas tank - it didn't leak until I replaced it 6 years later after daily use.
Another great use is to seal the bottom plugs on the offy intakes.
Maybe not the most elegant nor professional solutions, but it all works for me safely without any leaks.
