As KITT stops before approaching the cliff, the canyon floor they pan to is from Superman the movie.
Michael meets Bonnie and Devon at a bar called the Buckaroo Club. This is the same name as the bar frequented by Colt Seaver and company on The Fall Guy, another show from Glen A. Larson.
The private jet that was used is a 1968 Learjet 24 that has an Aircraft Registration No. of N664CL.
When KITT is pushed down the cliff with Michael passed out, KITT has the protective shell on to protect the Trans Am from damage from hitting trees and bushes. Look at the top of the windshield and notice the thickness between the glass and the roof of the car. The production crew designed and built a rubber shell to place over the cars when doing heavy stunts like going through brick walls so they wouldn't have to put the cars in the body shop constantly to keep them pretty.
This is the first of M. C. Gainey's two, unrelated appearances on Knight Rider. He can also be seen in season four's "Out of the Woods."