The ’66 was really bouncy when I first purchased the car, the shocks were completely shot.  Also, this car has limiting straps on the rear attached from the axle housing to the body.  These are strips of rubberized cloth that actual limit how far the body can move away from the rear axle.  Mine looked like they had touched the tires at some point in their life and were chewed up pretty badly.  I installed four new shocks and new limiting straps.  Now the car does not feel like it is going to roll over in the curves.

Products used:

• 4 KYB Gas-A-Just shocks
• Two limiting straps