Brake, fuel, flare fitting leaks.
Time for me to get flamed by the know-it-alls for passing on a tip gained by experience.
I learned this while trying to stop fuel weepage from the dual Holley fuel feeds, that came with the 9/16 fittings at the carb, you try and cinch up that last little bit, and the wrench rounds the nut off, even the near perfect Mac and Snap-On flare wrenches, which I feel are excellent tools.
What I found works, other than the little brass funnel things, is to, here it comes, you can't do that.
Teflon tape is not only a thread sealant but also a friction reducer.
If you put a coupla wraps of Teflon tape on the flare fitting male threads, ( oooow)
You'll find that last little cinch works, you'll feel the wrench smoothly tighten beyond what you could before .
It reduces the friction of the threads, allowing the nut to turn just that little bit more without binding, that stops the leak, without rounding the nut.
This works for brake lines as well, this helped when I used s/steel, which I will NEVER use again for brake lines.
So if you can't find the copper gaskets, a few wraps of Teflon tape, , ,
but, but, but, that's to seal threads, - look up Teflon tape on Google .
If this helps you, great, .
P.S. be sure to remove residual Teflon tape that's visible, or every person that spots it will point and say " didn't you know Teflon tape is only yada yada yada," showing what they don't know ,bs.
Flared fitting Copper gaskets
https://www.bing.com/images/search?...are+fitting+gaskets&form=IGRE&pc=MOZB&first=1
Let the flames begin.
Cheers