Sounds like a similar setup. Ladder bars, Ford 9 inch with 4.88 gears. 11.5 x 30 inch tires (Not enough clearance for bigger tires. Front and rear motor plates. Engine set back to #1 cylinder aligned with front spindle. 60 foot was usually around 1.46
There is way too much flex for what has been done to your car. If you jack up the left front with a jack about a foot, does the right side stay on the ground? It sounds like some serious twisting.