Hi Stephen - in addition to the Rock-si-Chord, the Bellagio studio was graced with the presence of a Hohner Clavinet, used on such
Sunflower-era recordings as "Susie Cincinnati" and "Good Time", as well as several cuts on the
Friends album a few years prior. The most popular model of the Clavinet was the D6, but since that didn't come along until 1971, I'm wondering which model or models might have been utilized by the Boys in the '68-'70 era...the most likely being one of the following...and I'm hoping you might remember, based on their pretty distincitve appearances:
model L:
https://www.youtube.com/watch?v=0rVx0wqXmecor model C:
https://www.youtube.com/watch?v=s55cKNmkshk