Rasputen, Based on limited experience with these engines, one complete tear down and rebuild. I would not suspect the #2 cylinder to be the "hot" one but rather the #4 - due to it being "more remote" from the water pump and return line to the rad. It also seemed to me that more "gunk = stuff settling to the bottom" occurred around the base of #4 - so I inferred "less coolant flow" at this location.
Don't know of any other issues which would cause #2 to "always" be the problem.
Not to take issue with your comments on #2 being the hottest, it just occurred to me that maybe ??????? it is the coolest. --- 8N is over-radiatored.
--- the return outlet in the head is just above the #2.
--- coolant systems without thermostat (sp) don't come up to proper operating temp
Just some thoughts, Jim