Can anybody who has these Wards fans tell me if I could still use my Rivco airhorns with these fans?

 

At least one member has mounted Trumpet air horns, https://www.hdforums.com/forum/touri...hog-horns.html not rivco brand, not sure exactly how it was done or the integrity of the mount, but this link might help. It will definitely require some custom fabrication, and it may not work at all.