There was another race that I thought you were writing about at first. I don't remember all the details but I believe it was with the new 427 race car. The scca would not allow it in the production class because the
oil cooler had not been on the homologated car so they took it off and he ran in the production race without it....and won.
Then they put the cooler back on the car and he ran in the prototype class with it on and won that too. That is how I remember it but may have some details wrong.