You guys are getting WAY off the subject. Let's fix the issue and then complicate it later
PCV? Nonsense. That carb should have enough adjustment range either way but it was designed to run WITH a PCV.
Dwell? You cannot change it (IF it is electronic) so don't worry about it. If you have points, set the points by the dwell, and a little "smaller" numerically to compensate for future wear.
Timing curve? You should be "for now" setting INITIAL (idle) timing so you can troubleshoot the problem, and if the curve is AFU then deal with it once you have solved the problem at hand. DO check and see if the dist is damaged, the advance stuck, or vacuum can ruptured.
I would "go back in time" to maybe 67 non CA and see what the idle / initial timing is spec'd and maybe even bump it a couple degrees from that
Make sure CERTAIN that the valves are adjusted IF THEY are not the newer "non adjust" types
Warm the car up FULLY. If it won't run at operating temperature, FIX that---missing stat, whatever. Adjust mixture with a tach or vacuum gauge. "Work" the carb into place with mixture and idle speed. That is, mixture and timing will CHANGE idle speed so as you get them closer to where they need to be, the idle will change. LOWER it back to where it belongs.
Adjust mixture to peak RPM when fully warm on your vacuum/ tach. You normally want to just "bump" the idle screw a tad clockwise from the peak "on the lean side" You don't really want the vacuum/ RPM to change much at alll when you do this. Get a helper, block the wheels, recheck idle setting in gear. BE CAREFUL and be safe doing this.
