It was more than 50 years ago when a young man, who grew up first on a farm in Iowa, then in Tulsa, Okla., came to Chicago armed with a college scholarship and a guitar. He’d spent many hours learning how to play blues licks on that machine and, now, he was going to be in the place where his favorite music came from. Elvin Bishop, later nicknamed Pigboy Crabshaw, was in hog heaven.“Blues…
