Thanks for posting the photos. Here are the Trans Am results.
http://www.1966shelbynotchbackmustang.com/TransAmResults/1966TAresults.pdf
In race #4 VIR brought in several NASCAR drivers to increase the crowds. #14 Barracuda is driven by Richard Petty. Finished 34th.
Ron Gable was brought in as a back-up driver for '65 Marlboro race, and is listed as a driver for races # 6 and #7 in the '66 season.
Here is his story with the second '66 factory Trans Am Dart.
http://vintageracecar.com/pages/thismonth.cgi?magid=12&magiid=24
The Miles car may be associated with regional level Trans Am SCCA events or tracks.