I am no guitar-playing nous, but as a fan, I appreciate this Acoustic Guitar issue with Glen Campbell the Session Musician pictured on the front cover (see picture below) and its lengthy feature article along with lessons--pages of sheet music (guitar tabs) and links to online videos. One of the special lessons is dedicated to Glen's playing of "The William Tell Overture".
The article's writer, Adam Levy, gets deep into the Campbellology of Glen's playing and describes it with adjectives such as "propulsive", "articulate", "keenly melodic", and "sometimes wry".
About Glen's musicianship, Levy writes: "Part of his (Glen's) genius as a player and songwriter was that he could take simple musical ideas and rework them in seemingly endless combinations." (Didn't we see these reworkings continuously on the Goodbye Tour when Glen played some tremendous guitar solos on his hit songs, each solo different from the previous shows' guitar solos?)
Levy ends the article with "Glen Campbell was always a h*ll of a musician" and "his dedicated fans have known (this) for decades."
I found this magazine at Safeway, a local grocery store that carries a huge selection of magazines.
(It can be purchased in print format or digital (PDF) on AG's website, too, at: https://store.acousticguitar.com/collec ... ember-2017
I have never purchased from this website so I can't vouch for it.)