Wow, 9 miles huh? And you didn't have to switch them, plenty of people run the calipers mounted to the rear with no issues whatsoever.
The common, off the shelf hose that works well if you mount the calipers to the rear is a front brake hose from a '69 Camaro with disk brakes. That hose is 15.7" long. The factory brake hose for a '74 Dart is 11.8" long. So the difference is less than 4". And it's not like you need some custom length hose, the solution is still a factory length hose. Just a different factory :D
The calipers work just fine mounted to the rear as long as you mount the calipers so the bleeders are up and you use the proper length brake hose. I've run the 73+ calipers in both locations, it doesn't make a difference unless they're interfering with the sway bar or you run the wrong length hose. The calipers don't care and there are plenty of ways to safely route the longer hose if you have a little common sense.
