Idleing Issues!!!!

OK, here we go with another gremlin in the system.

I have a 360 with a fairly mild cam, 650 edel. dual plane intake, electronic ignition, manual choke, headers. Ok now that I have most of the info people ask for when you post something like this Ill carry on! lol

I am unable to figure out why my valiant idles incredibly low after it has warmed up. When starting it, it acts just as you would expect. Use the choke and itll fire and then I have to slowly ease the choke after a bit. Once she gets up to about 180 or so it starts idleing low and rough. so much so that itll die about 50% of the time if left alone. Not to mention if I drive it, it will die for sure when I come to a stop in gear, that is if I dont left foot the brake.
So now here is what I have checked to start looking for the answer.
Plugs--- could not ask for it to burn any cleaner!
Elect. Ign. ---- Retraced all wires and all is good in da' hood!
Plug wires--- Good!
Cap and rotor----Good
Adjusted timing----No improvement. (should you get any rotation play when grabbing the rotor and twisting it?)
Adjusted carb-----Seems to be good, It didnt help much trying to lean it or richen it.

Here is what I am wondering about, this carb was on another car prior to mine (challenger) I think. The accellerator pump was unable to come all the way to its resting pos. making it idle to high and be unadjustable due to linkage restrictions, so I moved it one hole, now I am concerned that this may be part of the prob.

Also since I have installed the new tank, the filter up by the carb doesnt seem to have much fuel in it until after about 30 minutes of running. But the one back at the tank is constantly full. The vent for the system in my valiant is a tube that is at the top of the filler neck and drains openly near the frame rail.

Any help or ideas is much appreciated! thx :thumbup: