Varajet 2SE leak

[FuzzyBob]

Hi,
I seem to have a very slight leak coming from the "port" pictured here. You can get an idea of the amount of fuel from the paper towel. It so far has not been enough to pool just a coat of gas residue over the heat shield. It is only noticeable after driving while the engine is cooling at a certain point it stops and will remain dry while the engine is cool. The carb was completely overhauled about a year ago. So its very vexing. I recently changed the fuel filter and at first assumed that was the issue as evidenced by my over use of thread sealer.
Not sure what that port is? Mixture screw access? Though if so not at a very good angle for any kind of service, so maybe not. Is there any way to stop this without taking the card down?
Any info or thoughts would be appreciated.

Cheers