GMC 7000 series dumptruck help

I have a 1981 GMC V8 7000 series dumptruck. I need to get it ready for a CDL test and the 2 things I need to fix is the horn does not work and the hazard lights won't flash. I found a bad horn relay and got that fixed but I cannot find any flasher but what is in the fuse block and that seems to only affect the turn signals. Is there another flasher just for the hazard flash or do I have a bad switch in the steering colum? Please any help in the right direction would be greatly appreciated.

Thanks