Ignition Double check

Just want to double check my prognosis on an issue: I was helping out with a friends vehicle last night that began running rough. It turns over easy but does not fire easily and will buck when idling and has little power as if it were missing a cylinder, only 4 on this one. Eventually it would not start at all.

Voltage checked out fine and their carb has a window on the float so I could see fuel was getting in and the smell of gas in the exhaust proved that.

I checked the plugs and noticed the electrodes were quite worn so I cleaned them and re-gapped them. The car fired right up after that like normal, but after a few starts began its shenanigans all over. I pulled the plugs and they carboned up fairly quickly, not wet though. As it was idling roughly I pulled one of the spark plug wires and the idle smoothed out. Replacing it brought back the rough idle and removing a different plug wire smoothed it out again.

Obvious items I recommended were new plugs, wire, rotor, and cap. My prognosis was that coil was beginning to fail and was not strong enough to keep up with all 4 cylinders. I did not have a coil to test with as it was late and I thought my MSD super blaster II might light that little engine on fire. Seems like symptoms similar to when Jeff realized his resistance wire had failed and his coil was not strong enough.

What is this thing Brian? Is it electronic ignition? Devil's in the details a lot of times.

I heard "The Angel is in the Policy"...

1980 Datsun 210. Unfortunately they left their service manual at home. From what I can tell its a points ignition but I did not get enough time to pull the distributor cap. Perhaps I should check the gap and condition of those before pursuing anything.