My trusty civic has its driver's side AC vent missing for several years now. Today I decided to make my own replacement vent since these items are becoming increasingly hard to obtain for a 1999 vehicle.
Step 1: Creating Inner Walls for the Vent.
I used an old dog food bin to cut sections out for the inner walls within the vent. I want as much cold air channeled out. I used my handy cutting tool for the job.
Step 2: Sticking the Inners Walls in Place.
I used an unsung hero i.e. silicone adhesive to secure all the inner walls inside of the vent.
Step 3: Creating the Grill and Completion!
I cut a suitable shape grill out of a spare plastic basket. I secured it with silicone and now my car has a perfectly good always on AC vent!