Check out the VTR site under TSOA Newsletters. There is a ton of information and pictures of all the US racing and production TR7s and 8s. An article on the sliding glass sunroofs in May June 1976 for instance or extensive TR7/8 race car coverage including Huffaker and Group 44 and Slagle cars in OCT 1980.
Enjoy
http://www.templeoftriumph.org/tsoa/tsoa.html
Paul