Help! Please, vacuume line goes where?

[extrabitching]

Help, can someone look and see where this vacuume line is supposed to go? It fell off when replaceing my a/c accumilator/dryer and I can't see where it is supposed to go. It is just behind the battery near the firewall. It is the little black hose sticking up in the air, to the left of the blue thing. Any help would be greatly appreciated.
its a 5.4l year 2000

 

[FordandPolaris]

What year truck

 

[extrabitching]

year 2000, but should be the same for all gen 1's so I put it on this gen 1 forum. If someone could just go look where theirs goes, even shoot a quick picture that would be awesome. It is 100 degrees here ion phoenix and I think this is the reason that my front a/c only blows from the defrost, and warm air. I just replaced a/c compressor, accumilator and orifice tube and recharged and the rear now works, but not the front. It must be this disconnected vacuume line, but I cant see where it is supposed to be hooked to.