Jack the car up , driver side so 123 can be measured as desired, perhaps confirm 3 is running hot as well.

Mechanics breathe in exhaust fumes everyday at the shop, I'm quite sure it's fine for us budding wrenches to catch a whiff of exhaust fumes once in a while for the sake of our beloved car !

UPDATE: Cylinders 4 & 5 not firing
 

So, I did not revisit/re-measure the cylinder temperatures. But, my car was at an air-cooled shop for new CDI/Coil. So, I asked the tech to check the assess rough idle and check if any/which cylinders were not firing.

Turns out injectors were clogged @ Cylinders 4 & 5. Engine/car was running on 4 cylinders :eek::confused: !!!

He removed them, gave a proper clean, and re-installed.

Car/engine running smoothly now!!!

Peter @ Stuttcar Services in Pasadena is great! For those who are in the area, I would recommend Stuttcar --- make an appointment; the shop is busy.

If you have an exhaust tube that is way hotter than the rest at idle that can be a indication of a exhaust valve leak. I would recommend a leak down and/or compression test to rule that problem out. For a car that has been sitting for years I would start with all the basics so add in valve adjustment, Mixture settings, timing etc.

john