Probably the '66' K code convert would be in there but as Jack65 said, no real numbers. I think there were 256 '68' Fastback Deluxe (?) w/bench seats. 564 '68 1/2' GT hardtop w/428 CJ motor. 857 '69' Boss 429's. These numbers are from an undocumented source but interesting.
The 69 convertible GT would be the rarest of them at 1,127.
Here are the GT production numbers from Marti for 67-69,
67 coupe 6,545
67 fastback 16,212
67 convert 2,341
68 coupe 4,766
68 fastback 12,087
68 convert 1,986
69 coupe 1,483
69 Sportsroof 4,084
69 convert 1,127
The GT package was cancelled near the end of the 69 model year, it's popularity was over with, especially with the Sportsroof models due to the fact the "new" Mach 1 package was a GT with added goodies. The buck tags of Mach's list "GT" or "PIO" on them.
I have a book with the overall GT production at 15,079 for the late 65 model year and 25,517 for the 66 model year. No model breakdowns are available or known. You can see how the numbers declined, keep in mind that the GT was added halfway through the late 65 production. Not offered in the early 65s (64.5 to some) and not available during the beginning of the late 65 (true 65 to some) modle year. It was introduced in April of 1965, and the 66 model year went into production in August of 65, so it was only in 4-5 months of that year production. If you do the math that was quite a lot of cars in that time frame and that 15k would be quite higher if it was offered earlier on.
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