All A-body spring stacks fit all A-bodies, sometimes with very minor tweaks. Go give
ESPO a shout for a set of 5-leaf/V8 springs (say they're for a '65 Dart if you must, but I think they're hep), which will improve the spring rate without overdoing it like the Super Stock items would.
Remember to
aim your headlamps after you replace the springs, or you'll only get to see 3 feet in front of the car at night.
