Did these trucks have dual horns?

[Tom Vogel]

Ive got a 72 2wd Jimmy with a Cheyanne package. When I took it apart to restore, it had the 2 horns you see in the picture. I sent them off to restore, and the guy at the horn restore place seemed to think it was unusual for the truck to have dual horns. Well, I got them back and began to think, maybe someone just stuck an extra horn on here.
Whats the story/opinion of the experts on here. The picture you see is how the horns that were there were positioned. Is that right or no. ??