70 Dart with factory sway bar ?

I’m ordering parts to rebuild/upgrade my front suspension. All the kits I looked up for a 70 with disc brakes also come with the bar to k frame bushings. Did the two come as a package ? Was it an option?
Also I’m considering poly bushings except for the moog upper control arms offset bushings for more adjustability. Other than “squeaking” what advantages/ disadvantages are there to poly bushings ?



kilooked up for a 70 with do