Where is the low pressure port for freon refill? on 2002 Ford Expedition

I can only find the high side evac port.

Asked by for the 2002 Ford Expedition
where do u add freon
its by the passenger side headlight and has a black screw on cap on it. It is the larger of the two.
Hate to tell you, but the large black-capped port is not the place. Neither the gauge for pressure testing nor the hose fit this port. Supposed to be a smaller blue-capped port, but cannot locate one on this vehicle (we have an F-150, a Freestar van and a Mustang besides the Expo so we are not Ford virgins).