The gap back to Dixon was just 0.093s.
Pruett was delighted to score another pole position, admitting that he'll take as many of these while he is in the twilight years of his career.
“I don't know how many more years I'll be doing this, so I'll see if I can start up near the front as much as I can,” he said.
“We knew we had a pretty good balance with the car, but I knew I had to yank one off. I gave it all I had, and took a few chances going through the bus stop. Winning the pole is big for us.”
Dane Cameron qualified third for Team Sahlen's at 1:41.213s in his BMW/Riley. Michael Valiante was fourth and the fastest of the two Ford-engined Rileys entered by 2012 Daytona 24 Hour-winning Michael Shank Racing team.
Nick Tandy won his first Rolex Series GT pole with a lap of 1:47.631s in the Konrad Motorsport/Orbit Porsche GT3.
Porsche Cayman driver Shane Lewis will start at the head of the GX class runners – the first time the class has run in the classic race.