A back space issue, plain and simple. If it rubs either static or with a turning deflection try a 1/4" wheel spacer on the front to clear the tie rod ends.
Mark:
Where are you going in NY? If close to me we can connect for a beer at my Vet's Club in Cooperstown, right across the street from the Baseball Hall of Fame.
Pulling that selector unit and replacing the o-ring should be a pretty easy job. Check the feel of the shaft, it might need some polishing. There's not much to it.
So far I think 2. I had a good opportunity to grab all sorts of parts off one crushed in a barn collapse many years ago and have used a few over the years as necessary. I also got some running gear off a wreck but I think that hasn't been...