Wow this doesn't look good, how about a scarebird disc brake swap?

https://scarebird.com/index.php?route=product/product&path=64&product_id=134

56 Plaza 63 D100 step side 67 Coronet, 68 Roadrunner, 69 Super Bees, 69 Coronet 500 convertible, 70 Roadrunner Post, 79 D150 360, and a severe case of Mopar a,d,d