I'm getting ready to order a set of reproduction Eaton leaf springs for my '69 Mach 1. Looking at the NPD catalog, I noticed that the leaf spring application chart lists a "Competition Handling" leaf spring for a '69. Was the competition handling package an additional option on top of the Mach 1 package, or did all Mach 1s automatically include it? There was nothing on my Marti Report about a competition handling package, and I just wanted to be sure it wasn't something that my car was originally built with.