Bought a used 69 Dodge in 1976 with a big block and totally stock, points style ignition.
Car would start fine and ran fine until the temperature got down to about freezing, then it would not start if left to get down to ambient air temp. If put in the garage to warm up, it would start with the starter motor, otherwise you had to push it to start. (4-sd.)
After dealing with this for 2-3 months, started looking at everything and decided to replace the coil thinking it was "weak".
Found the previous owner had a kill switch wired to the coil and the leads were re-installed on the coil backwards. Switched them back and everything was fine.
By the way,it only had 8,300 miles on it, I still have it ,it has 27,000 on it now, and the original coil is still in it.
Most puzzling thing I ever saw.
The original owner never had a problem because He only drove it on nice summer days. I knew the car since new, bought it from my cousin, the original owner.

Jay