By Matt Hladik Legendary race car driver Dale Earnhardt Jr. is typically a NASCAR commentator for NBC, but FOX is borrowing him for today’s GEICO 500. Earnhardt Jr., who has also contributed to NBC Sports’ Super Bowl and Olympics coverage, is in the booth this afternoon with FOX’s Mike Joy and Clint Bowyer. They are calling the action from Talladega Superspeedway. Because he won six times at Talledega, Earnhardt Jr. seems like a natural fit to call this race. Combing through Twitter, it seems like many racing fans think he is a natural fit with the FOX contingent in general. Earnhardt Jr. won’…