Thanks for the Wrecking Crew mention - mighty talented studio group in many variations...and always led by the great Hal Blaine.
Speaking of which, a friend of mine is a critically acclaimed mastering engineer who, for many years, had a weekly breakfast with Hal Blaine and others in the biz.
BTW, the Wrecking Crew were the musicians on the Beach Boys albums so obviously Glen was on some of those recordings. Not surprising when I saw the BB, Glen was on guitar during Brian Wilson’s drug daze.
The book portrays him as having played on the most records. He comes across as a very nice guy, cheerful and witty.