The rear suspension featured independent wheels, trailing arm/A-arm, double helical springs, double coil-over hydraulic shock-absorbers, auxiliary rubber springs and stabilizer (sway) bar.
Here is a quote from June 1970 Motor Trend "At the rear, the suspension uprights are aluminum castings. At the front, they're stock American Motors spindles, ball jointed to special suspension arms. Also part of the design is a complete AMC steering linkage with Saginaw made steering box and column." The front suspension was independent front wheel with helical springs, single coil-over hydraulic shock-absorbers, unequal length A-arm and stabilizer (sway) bar.
The suspension on the AMX/3 reproductions uses C4 Corvette parts.
There are lots of aftermarket parts upgrades for the C4 including Bear Brakes and Bilstein shocks.