Good idea. Maybe he should have sang ALL his lines, like an operetta.
Wayne may have suggested him after a drink, or eight, or ten.
I recall seeing Campbell on the Tonight Show to promote the movie and he complained that Duke insisted he ride a smaller horse. Of course, there was that line in the script about him being mounted on a sheep. Maybe Glenn was just being cranky. Rhinestone Cowboy, indeed.
We deal in lead, friend.
