Do you have fuel pressure regulator? I didn't have one on my DCO for years because I read that with the Carter fuel pump a weber shouldn't ever need one! That was here:
http://www.racetep.com/webfuelspark.html
Well after years of battling fuel dripping into the throat of my carb I finally put in a nice Holley FPR and set it down to 4psi. Wouldn't you know it, the dripping stopped and nearly all the problems I had been battling since I put the weber in were solved.