Little Holley help please

I pulled off my 1406 to try a holley 1850 on my 318. Anyways I have been tinkering with setting the secondary idle screw ( the one underneath ). The carb to intake gasket is wetter than heck. What would be causing this.
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The gasket is gettting soaked from the inside out. Also any good tips for adjusting the secondary idle screw. The carb seems to run fine while driving, the A/F is around 13.5 to 14.5
but at idle it is 11.9