Heavy-duty front/rear spring option ZN1 documented on one Canadian COPO example; not asserted universal
suspension · optional
1969 Chevrolet Camaro Yenko COPO 9561 photographed by Sicnag; reviewed as COPO 9561/Yenko dealer-branch exterior context, not individual-car proof. 1969 Chevrolet Camaro COPO 9561 L72