Choke doesn't seem to work as it should

Sorry for the delay in getting back to this. I went at it again this weekend. Initial timing is at 15 degrees with the vacuum advance disconnected and plugged. I pulled the carb and reset the primary curb idle so the transfer slot was just exposed. I had taken it well past where it should have been in order to increase idle speed to keep it from dying. Float level seems to be OK. I reset the idle air screws to 2 turns out and then set the base idle speed with the screw on the secondary. Now the manual choke seems to function correctly. I may have screwed up the start up process once or twice but typically I do pump it once before starting and have only recently needed to use the choke.
The car is also more responsive at throttle tip in, doesn't hesitate like it was before so I made some progress. Now, I have an issue (it seems) with the idle air screws. Using a vacuum gauge I see very little change when adjusting them. I have ~14/15" of vacuum at 900rpm in gear. Adjusting the screws doesn't seem to affect much going one turn either way from start. What I see now is with the idle set so it just barely doesn't die in gear at 900rpm, it is about 1300rpm in park. This is fully warmed up and choke all the way open. I know I should be able to get the idle lower with this fairly mild/stock cam. I'll admit, I haven't touched a carburetor in 30+ years and wasn't that good a tuner back then either, so I appreciate your help and patience. Running out of time to get it better because it goes to storage later this week so any other words of wisdom are appreciated. It drives pretty good, just doesn't seem to want to idle real well in gear.