The West Seneca, NY owner had a sign that touted the car as follows...
"Prototype of Bill Jenkins First Factory $$$ sponored Drag Car GRUMPY'S TOY. When Jenkins refused to run a big block in his Nova in 1967, Chevrolet switched to Yenco for the Chevelle, Nova and Camaro factory sponsorship." The sign also claimed "NHRA A/Stock Eliminator 1966-67"
And yes, he spelled Yenko wrong