383 Wont Idle with new to me 800cfm DP. Idles and runs ok with Edelbrock/AFB

340dartley said
Maybe I need to try and describe the Symptom a little better or at least with more detail. When I initially installed the carburetor, it would not idle at all. I could keep it running by holding the throttle open. Using the idle speed screw I turned it in until I was able to release the throttle without it stalling. This was at a about 1800 rpm.

A carb that is runs nice fully warmed up, will need to be held open when cold. Running the screw in to get it warmed up is common procedure.
What we don't know is if this is really the case, and the eddy you had on it was too rich.
However with that cam, its going to want richer carb feeding cold or hot.

340dartley said
I then screwed the idle mixture screws all the way in and then backed them both out 2 turns.

This must be because the idle port isn't restricting the fuel. Throttles are still too far open at idle.

340dartley said
As far as initial timing, I will have to recheck that. I set it at 33 degree total timing at 2000 rpm. I did not suspect a timing issue as it runs normal with the old carburetor. For the record the distributor is an old Mallory Dual point with no vacuum advance.

That's a logical conclusion. Not really knowing why the old carb did well or what the timing is at raises the question. Timing and fueling go hand in glove.
With no vacuum advance, the 33 at 2000 might be fine. or maybe it could use a little more.
Definately check timing at the low rpms, and also at 3000 rpm. Depending on the springs, it might still advance a few more degrees as the rpms climb. That would be OK.