to address #3, yes the columns do have bearings that wear out. Ford sells a kit to rebuild the column and it comes with instructions HOWEVER, before you go through the hassle, pull the plastic covers off and inspect the actual steering shaft. On one I rebuilt, the shaft was so worn from being used with bad bearings that the actual slots the snap rings sit in were basically gone. I ended up having the tack weld the snap rings to the shaft in order for them to hold. Ford also sells whole columns and they are not that pricey. They were used for many years and are available.

 

 

I think you figured it out. Maybe that line that's open in the video is the intake to the AIR injection system (for the cats). I'm not sure, my 96 f150 doesn't have that system so I don't recognize it.

 

On my 94, the nipple on the oil filler is connected to the filter in the lower half of the air cleaner box. the center nipple on the vacuum tree is connected to the brake booster and the forward single nipple on the manifold in connected to the PCV valve on the passenger side valve cover. I know the pictures you have show it going to the back of the intake, but mine does not even have an opening there for anything. May have been a running change during the model year.