So I wish you lived near me and I would loan you my A/F gauge and sensor. That $130 device took all the guesswork out of my carb tuning and I was able to get a Eddy 750 to function cleanly and without a lean stumble on a 440.

If you are not in too much of a rush, I would consider doing something like that. Amazon sells them for less than $150 and it is an excellent tool for doing exactly what you are doing. I got a local shop to weld a couple of O2 bungs in my exhaust and it cut my carb tuning time and guesswork down to something very manageable.

I don't have the wizard skills to read spark plugs to the level of knowing where the A/F mixture is at Idle, cruise circuit, low-vacuum cruise and WOT.

I am sure there is a wizard here who can look at the photos and tell you what to do since there are some very very smart people on this board like Mr. Cab. BUT, if you have a few days to get in a gauge, around $150 and a local welding shop to install some bungs I can guarantee you will find a solution pretty quickly.