Here is another image of the first clip design compliments of Big Iron from a few years ago.
Also, this is the lever on a 68. There was a service replacement part used for both 67 and 68 applications available that you could buy through the dealer but was discontinued in the mid 1990's. The replacement was black but used the same switch, wiring harness and arm. The plastic end was redesigned. I have one somewhere I could dig up if someone needed to see it.