670 Street Avenger running rich

Haven't been on here in a while but I have a 670 Street avenger on a Mild SBC that is running real rich at Idle. I have read MANY articals saying this is a common problem. Well what the hell was the FIX ! Lol ! nobody actually has said "That fixed my problem Thank You !" most threads end without and answer.....I have gone through everything I have read about setting up carbs and at 1 time i personally thought I was pretty good "Back in the day" but not now....Is there anything actually wrong with this series of Holley? ANYBODY got any positive input ? Thanks everyone. Tim
UPDATE ...I have gone the regular gambit of PV, Jet and Gasket changes all the way to new metering block.