I have a 360 magnum and I'm running a quick fuel super street series 680 cfm vs carburetor on a dual plane edelbrock rpm air-gap intake manifold and a 1 inch 4 hole phenilic carb spacer.
Over the last couple days I noticed my idle was starting to get rough, so today I decided to try and see if I could figure out why, I go to put my vaccum gauge on the manifold vaccum port on the carburetor and there is fuel on the rubber nipple covers. So I tightend down my fuel bowl screws a little tighter.
Then I went to see if it was running right and it wasn't, it accually felt worse, The only thing I can think of is the fuel that was leaking must have hit my carburetor base gasket and it broke the seal, Is this possible? is my thinking correct? Because if it's not then I have no clue as to whats going with it.

I would pull the carb & a good visual & replace the base gasket/check carb screws (dont overtighten). EDIT since the idle changed when you cranked on the bowl screws I would first check/replace the bowl gasket which would be even easier than replacing the base gasket

It's acting like there is a vaccum leak or there is a plug fouled, it feels shakey and the idle is all messed up. I'll go get a new carburetor base plate gasket and pull all the plugs and check them out. But I cant get any fuel bowl gaskets today. None of the parts stores around me carry carburetor parts.
I didn't over tighten the fuel bowl screws, I just got them tighter then they were. I have only had the fuel bowls off maybe 5 times, and I was told these blue re-usable gaskets can go for a long time.
I'll post what I find.