Lee Grey (Los Angeles Sales District Manager for 1968; "father of the GT/CS") once told me that lots of Mustangs, T-Birds and Galaxies were heavily "optioned" out by dealers in the L.A. area. Mustangs were sold in 1967 in "rainbow colors", painted right over the original paint! This thinking is part of what led to the GT/CS idea, and how it was another optioned out type of car for the L.A. market (although Northern Calif. had to OK the whole thing before Dearborn would approve it for production).
So, I am not suprised at all by the cars with tops--and no mention on the Marti factory report. Good thing for the Registry to keep track of these things, huh?
Also--look for NO seams on the upper windshield pillars, which adds to it being "original". Later tops used separate strips for the windshield pillars, to save material. The top seam was original, tho', whether original or repro.
Paul.