I’ve been searching on the site and just may not be looking in the right place, but what exactly did the heavy duty suspension option consist of for 67 model year? I saw a couple of things about a 7/8 sway bar but nothing else about other components/parts. Just attempting to gather info about my 67 convertible so I can keep my eye out for parts I am missing. It is a 390 car non GT, but it lists the HD suspension as an upgrade.