Another All-Pontiac Stock final was in 1977, @ Indy. Mike McKinney won it, in the original Truman Fields '68 Bird that had also won in '73.
Mick Leiferman was RU, for the 3rd year in a row.
http://www.nhra.net/50th/results.asp?mYear=1977
There were also 3 Pontiac powered SS winners that year ! John Herslow won the Grand Nats. Bob Michael won the Spring Nats. Sonny Ray won the Sports Nats.
John Herslow would have been driving the Herslow & Morlock SD455 '73 T/A record holder. Sonny Ray would have been driving his '72 GTO record holder. Bob Michael has had so many Pontiacs, I don't know what he was driving. I assume it was his '73 SD455 T/A, before he sold it to Don Kennedy.