Lar, the Chevette suspension is a very light weight suspension for a lightweight car. The only two/three GM cars to use this suspension are the T cars (Chevette and T1000) and the Pontiac Fiero (with the weight in the back). It is what it is. If you are having no problem with it, drive it as is and enjoy it. But watch for cracks at all mounting points, especially the spring mounts.

Chevettes were less than 1800 Lbs and the suspension didn't have to support much. The same is true with the Fiero (but doesn't tell you something than Pontiac changed the suspension in '88?). The Mustang II weighed 2500 to 2800 lbs, so the suspension will take far more abuse. But there is a limit to everything. You don't see Mustang II suspension put on full-size cars from the mid-'50's on, do you?

Good luck with your car!