This 2016 documentary about The Everlys was on BBC this week. Keith is one of the interviewees and there are a few quotes from him scattered across the film, plus a small discussion of the 1963 Everlys tour supported by the stones towards the end. It's a good doc.
I'll look for this. They have always been a fave listen of mine. Their "Wake Up Little Susie" was the first record I ever bought back in the day, 45 rpm. There is much to be explored beyond the hits in their catalogue of music.
Re: Semi-OT: The Everly Brothers - Harmonies from Heaven