Suburban rear A/C expansion valve location?

[1998_K1500_Sub]

We put the orifice tube in the line by the evaporator core just like on pickups, but there wasn't one in there to begin with. So are the Suburbans not supposed to have one there and have it instead in the location of that diagram or should it be in both?

(for someone's benefit in the now or in the future)

The orifice tube on the Suburbans (with rear AC) is just after the "Y" split (the "split" for the rear AC) in high-pressure line. Physically, that "Y" is not far from the (passenger's side) battery.