It's not too late to build a four link rear end setup that the Motown Missile used.Interested to hear more.
I'm just about done with my 72 Dart Swinger. Full drive train rebuild and upgrade. 3:55 sure grip with disc brakes, dropped 1 inch 5 leaf rear HD springs, .990 torsion bars with hellwig anti sway bars front and rear, Bilstein rcd, tubular heim joint upper control arms, re inforced lower control arms, k member welded, steering box is a stage 2 firm feel rebuild, power. Doug's full length headers into 2.5" exhaust, thru Gibson mwa mufflers, if you could call them that. 904 trans with 1st gear planetary replaced with shorter ratio, 3.98 in first gear. 2200 stall built by pro trans. 18" wheels, nitto 555 g2 18/35/265 front and rear, can and will put bigger rubber in the back a couple weeks after getting it on the road. It's gone have a problem with traction and the asshole on the go fast peddle.