So I am not a NASCAR expert but lots of things on the shirt lead me to believe it is an actual pit crew jersey for Dale Earnhardt Sr. Made in USA by Bowlers Shirt and Uniform in Los Angeles. There is a Velcro piece between the buttons where the GM logo is which wouldn’t be on a fan type shirt. Happy to answer any questions or get feedback from those that know more. Does show some staining see pictures for details. Measurements included in pictures. Vintage larges are usually smaller then today’s L