I am still leaning towards a vacuum leak
Before I changed everything out I was reving at 1000rpm in park and around 700 rpm in drive now I have to keep it reving around 1300-1500 rpm or it will stall in park
My 6 pack did the same thing until I got all the carbs setup close.I still have to run a touch rich to keep it from dieing when put into gear because my cam is too hot for a stock converter.So a stall is in the near future.Anyway I had to pull the lead plugs out to adjust the outboard carbs and make sure you have the correct base gaskets.It very well could be a vacuum leak but mine was doing the same thing.
Side note it would be interesting to see how many AAR and T/A were built with an auto as it seems they work better with a stick.