I'm aware of some of that group, certainly not all of them. Some ZL1s dropped off the radar in 1969, never heard from again.
As for #59, found intact in the '80s w/o engine. Believe it only showed a few thousand miles at that time. It's the ZL1 that had white D96 stripes on one side, black on the other. Featured in the March 1987 Hot Rod, again in Hemmings Muscle Machines May 2009. The Hemmings feature states they "over-restored" it but made several errors in doing so. Maybe they have since been corrected.