I did subframe connectors first just 2x2 so I didn't have to cut the floor. It made a HUGE difference in the feel of the car. I recently added a 6pt. bar and was suprised it felt even better!

Anything you can do to stiffen our unibodies helps!

'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.