It's best to buy the duck hose you need from LMC Truck they're online also keep in mind that the left hand duck hole is not a hose its a plastic runner that goes from the vent to the AC blow box also the more likely reason your air is not coming out of the top and only the bottom, and this is...
Q: what does the vacuum can run to.
Thx: I now understand that vacuum line is for my HVAC doors. Ironically my AC only blows out the bottom. No Sir out of my vents.
Q: what should that vacuum line be hook to
I guess the other owner chopped it off, reason there's only a nipple of a vacuum line...