Well, Id find a 73+ front crossmember (maybe score a swaybar also). Rebuild it, or put it on as is. Be sure to grab prop. valve and MC (id use the MC as a core for a new one).
cut a coil off the front springs (lower ya about 2")
Reinstall with grade 8 hardware
for the rear, you do have coil springs?
Id score some dropped springs (4") off here or ebay (80-110$) you can make your own shock relocators) and find an adj panhard/or make one.
http://67-72chevytrucks.com/vboard/s...d.php?t=359399