Munchie-Crunchie

I have an 86 dl wagon and I am having some carb issues. When I start the car up it acts like it runs out of gas, if I tap on the carb and start it again it runs. When it warms up it runs way too rich, I can actually see gas dripping in the secondary, and it stalls out. I have rebuilt the carb and adjusted the float level many times but nothing seems to help. The carb has been messed with before so I'm not sure if I should Just get a junk yard carb and start over or if I can revive the old one. Any help is greatly appreciated. Matt