1966 Dart Convertible 273 HiPo Very Rare Mauve Color Garage Find

Jim Lusk said
Figure something less than 10% convertibles

In 67 it was 2.41%
In 66 it was probably similarly
So conservative estimate would be less than 5% convertible.

According to Allpar only 83,626 darts were made in 66.

Based on 67 percentages that puts a 66 dart convertible at around 2018 built!