Slant 6, auto, with a 7 1/4 and 9" brakes could have come with 4" bolt pattern wheels up through 75 or early 76. Apparently, Mopar had a pile of the 7 1/4 rear ends and front 9" brake drums left, so they unloaded them on the Darts with the slant 6.

One time I bought a 75 or 76 4 door Dart with the slant 6, had the 4" pattern with the 9" brakes. it also had a 3:23 geared 7 1/4" Sure Grip with 9" brakes and the 4" wheel pattern. I think the Sure Grip was the only option on the car, it was very stripped down. It also had a blown up slant 6, # 5 piston and rod exited the block and killed the starter. I pulled the end of the rod off the crank, patched the hole in the block with some clear plastic epoxied to the block, replaced the starter and sold the car to a guy that needed a car bad. He drove the slant 5 for almost a year before he was able to get a better car. Gene