Thanks for this. Super helpful. Now was I supposed to cap the vacuum advance when I was getting my intial timing? Or is that only if my car is stalling out when the hose is disconnected? I just disconnected the hose and both the hole on the carb and vacuum advance were open.
it won't effect timing if you had the rpm correct. It could effect idle mix and rpm if the throttle was open too far. More of an issue with later cars like yours with higher idle speeds. But if there was no vacuum on the post, then its OK.