The_Beach, this site may be of help to you; not sure if it is complete/accurate: Glen Campbell Goodtime Hour Episodes with set lists.
Home page:http://www.tv.com/shows/the-glen-campbe ... /episodes/
A printable episode guide (that can be downloaded and saved as a searchable PDF file):http://www.tv.com/shows/the-glen-campbe ... rintable=1
You could do a cross check between Glen's recorded songs (see Rob's Songbook here on Glen Campbell Forums) and the songs performed on each episode. The instrumentals from the concert segments on the shows (with Jerry Reed, Larry McNeely, and others) may be missing?
I am sorry ... this cross check would entail much work. Perhaps each show's set list could be copied and pasted into an Excel spreadsheet and then sorted alphabetically?
From an episode broadcast on March 21, 1972, there were two songs that have only been performed live:
"Hello Young Lovers" (solo)
"In the Shadow of the Pines" - Glen and his parents