If your EGR valve is stuck open all the time, the car will run very lean, especially at idle. Using the choke will mask this to some degree. Remove the EGR valve and clean it in kerosene (or similar) and make sure the valve is opening and closing fully (it is noramlly "closed" due to spring pressure). Sometimes these valves get burned and will not seal completely (and you'd need to replace the unit)....but usually, they just get gummed up with carbon. In a pinch, you could remove the EGR valve and plug the manifold port that it attaches to.
Another thought: If one of the floats is stuck, the car could be running off one carb (because the float chamber would be empty in the "stuck" carb)....and the car would run lean. Try tapping on the float chamber with a small wrench to see if you can "un-stick" the offending float.
Another idea: to find vacuum leaks, start the engine and get it "idling" as best as you can. Spray WD-40 around the manifold gasket, the carb gasket, etc. If there's a leak, the engine will slow down as it sucks in the WD-40 (the WD-40 won't hurt anything....but it doesn't really burn like gas, so the engine slows down)