Likely Laguna Seca free practice. If one looks very carefully, the small rear spoiler is seen in place - something that would be thrown out in tech. and reappear at Dallas before the rainout was declared.
One of the greatest races ever for Pontiac but nobody at the General lost only one Word about it : Stupid like today when they closed down Pontiac forever
This is the TR-250 in '68. Note the black helmet with white trim & reversed 44s, which was part of the team livery that year. '68 was the only year we ran a TR-250, (really a TR-5 because it ran fuel injection). The TR-250 was my favorite Group 44 Triumph. The same car was a TR-6 in 1969, but I liked the TR-4 body better
This must have been an unusual open practice as the TR-250 is following Jerry Truitt's G-Prod MG Midget. Jerry ended up driving an MGB for Group 44 in 1970 and 1971 if my memory is correct