Ray Price, Roy Clark (he also drag raced hemi mopars) Little Jimmy Dickens, Charlie Pride, Willie Nelson, WaylonJennings, Alabama, Faron Young, Buck Owens and the Buckaroos, Earnest Tubb, Carter Family and a million others. My grandfather was friends with a lot of those guys.
One time I was at my grandparents house and Jimmy Dickens called. I had to tell him about the little perch I just caught. I was 3 or 4 years old. He was super nice to a little kid. Got a picture of my dad dancing in a diaper in front of the Grand Ole Opry stage while my grandma, Kitty Wells and another unknown lady are sitting on stage watching.