Have you checked the wire going into the air filter horn?
This is the outside air temp sensor. If this wire is broken or disconnected, it will think it's REALLY cold outside and will make your engine WAY too rich. This is quite often a problem on rich-running cars.

If you disconnect that, and it still acts like crap, that's it. If it runs worse, or if you see the idle speed change, then it's probably not it and you can move on.

Timing should be 5° ATDC WITH the vacuum connected. Some mechanics ignore that last part and set it to 5 with it disconnected. That will kill your power and make it run like crap. Also, if you've been fooling around with the points, you WILL need to re-time your engine. Changing dwell changes the timing.

Other than those simple things, when it's still cool and running like garbage, shut it off and pull 2 random plugs on different DJet circuits (not 1 and 5, or 4 and 8, or 6 and 3, or 7 and 2, but like 1 and 4, or 1 and 2). If the color isn't uniform, or if one has gas on it and the other doesn't, pull the other plugs. It's possible you have dirty trigger points. This can cause way too much fuel to be poured into the cyls, as I've had happen to me before, and the car runs like absolute garbage until it's warmed enough to thin the oil film out. It would repeat when the car sits for a while to cool down. Fix for this is to pull the dizzy, then take the trigger points out and clean them off with a paper towel to remove heavy oil deposits, then a business card between the points to remove the last bits of dirt and oil. NEVER SANDPAPER!