Picky? No.
From the days when you could smoke on an a/c and the IFE was an 8mm film projected on a screen, my uncle observed that: "If you want two seats together in Economy, where smoking is permitted and you do NOT want to see the film and you want to be on the NON sunny side (to get more sleep) ... the 747 is six seater aircraft."
That was the -100 where the last three rows were two seats due to the tapering of the fuselage and met his other criteria.
I think that some carriers put the boxes under the A + C and feed three seats from two units, some have a box for each and some one box for the row. The placing varies and, personally, I would not expect any of the seating laying web sites to be able to answer this with accuracy.