One side blue other side cool - puff of smoke

1974 850
I have noticed lately the right side header is bluing. I started the bike last night. As it was idling, I felt the pulses from the exhaust. The seemed equally strong but the right side was noticeably hotter than the left. I also got a few puffs of smoke from the right side when starting and a little bit while it was idling. Also got a couple of 'pops' when starting. I shut it down and did not ride it.

Both spark plugs look the same. A light chocolate brown color.
I have a single Mikuni 34mm carb
Pazon electronic ignition. Statically timed.
I checked that the carb mounts are tight
The exhaust nuts are tight

The bike had sat for 20 years. The head was sent out for new valves and a good cleaning. I did not remove the jugs. The cylinder walls looked perfect when I had the head off.

Can I just swap the coil wires to see if a coil is the culprit?

Any other troubleshooting steps I should do to determine what is going on?
If it is not timed properly, can this be the result?

Impossible finding if spark plugs and mixture flow are the same on each side. So logically try switching components that aren't shared in common. Think about pulling head to check head seam gas escape routes on smoke side. Ring bore also comes to mind. Can't be fully equipped Nortoneer w/o some new plugs on hand to switch in in case one side fouling mis firing.