Went by the Unser Museum while on vacation in Albuquerque last week. Saw lots of neat stuff.
Fun fact:the USAC championship used to also include races on dirt throughout the season. This is the dirt car companion to the Johnny Lighting Indy Car. In 1970 Al Unser won every event on dirt with this car, in addition to the Indy 500, on his way to a USAC championship.