727 with 3400 stall will not idle in 1st?

Sounds from personal experience like a case of not enough initial timing. What is the amount of your mechanical advance, is the vacuum advance hooked up and if so to what port on the carb (above or below the throttle plates). Likely you need to limit the mechanical advance which will allow you to increase the initial timing which will in turn smarten up the idle and prevent it from stalling when put in gear. What is your initial and total timing?