There is a lot more to making these car handle properly.
Here is one of several books that can help you understand what goes on with these cars.
GM did a very poor job with the front end geometry. If you look at the way the upper a arm wraps over the frame you can see that deflection of the front suspension will cause an increase in positive camber. This is why these cars are notorious for wearing the outside of the front tires. Plus most of these cars came before radial tires came about.
The first three generation of Chevelles need aftermarket A arms with provision for correct camber and additional caster. The fourth gen (73-77) like mine use the big car suspension so don't have this problem. They benefit from much larger sway bars and big wide tires.
Brakes are another issue. More severe with a BBC. When you do brakes make sure you use a complete system. Mixing and mis matching is asking for problems.