Tire discounters can’t align my Dart.

The missing elephant in the room, is, DID YOU TELL THEM what specs to use? Unless you are using bias tires, you do NOT want the thing aligned to factory specs, and many of these computerized in/out shops cannot seem to do any different.

Review this:
Turn of the screw: front end alignment for performance...

The so called "skosh chart" has been re-re-re-reposted here many many times
A good alignment shop or mechanic will know or be able to compensate for the tires design. A short road test after proves the work. Most businesses these days are blow it out the door and get the cash. Then you go back a week later and they say you hit a pothole or something and want to charge you again, even if you call right away when you get home or the next morning.