Chassis Stiffening - which kit? Cage?, Stiffening before paint, need help. Options

[corpselaurel]

I have been reading and searching. So far I have eliminated the boxed trailing arms.
I want to stiffen the car up before I paint. What 'kit(s)' should I install?

I have read read that most of the pieces in the chassis stiffening kit are useless. Should I buy the kit and install the others?

I have also read that engman's kit helps a lot. And I was also considering the Inner Rocker Panel Frame Stiffeners.

I just don't know which combination I should install. Should I use all of them or do some cancel each other out (for lack of better wording). Post links to suppliers if you mention any.

I am open to the idea of putting a cage in but it has to be in kit form. Does anyone sell one and would I still need any of the stiffening mentioned above with a cage?

The car is not badly rusted except for the battery tray and underneath - completly gone. I will be repairing it. My plans for the car are daily driver with some autox. Next year I will swap in a more powerfull engine. Thanks for any help.

[Eric_Shea]

I have them (boxed control arms)... I don't think they're good or bad.

From what I understand they're fairly useless. The factory did it to chase after rear flex which was eventually found to be in the bushings. I really don't see how the extra stiffness could translate through the factory rubber bushings... they're quite substancial.

Now, if you had roller bearings then it might add to the issue but with stock bushings I can't see it.

Regarding the chassis kits... I have the basic factory style kit pictured above. I've heard good things about the inner longitudinal kits but no experience.