Sounds like your throttle shafts are worn out and need to be rebushed- is there any up-and-down or back-and-forth movement to the shafts? Worn throttle shafts would explain the fuel drips, and when running is just a big vacuum leak- which may be part of your idle issues.
Instead of replacing, consider sending it off to be rebushed/rebuilt by a reputable carb rebuilder; for instance Woodruff Carburetor Specialties, a member here and a site sponsor. Plus, he's sort of local to you... Contact info is at the top of the sidebar-->
If you were happy with the carb when it was functioning well, I see no reason to replace it with a new one (possibly of dubious quality and probably questionable price...) and have to go through the whole tuning/setup process all over again.