4age oxy sensor placement

[antsmr2]

Hi not having a 4age exhaust manifold infront of me, just wondering where does the oxy sensor sit ?

Does it measure the gas from 2 cylinders or all 4?

[Ae92typeX]

on the 16v it sits near the bottom of the cast manifold, measuring from all four.
on the 20v its a little further down...I believe its still from all cylinders, but someone with one thay have looked at recently can confirm this.

[no_8wire]

I have both in front of me and it is as said above.