I upgraded my fuse box to Engman's modern version a few weeks ago. Very nice piece of equipement by the way... Problem is, my horn is dead sometimes. The wiring is fine on the steering wheel and up to the horns and I'm thinking that maybe a relay is being pushed on or has maybe gone bad. Is the horn relay one of the ones on the fuse panel?

The horn relay on my '74 is one of the relays on the fuse panel.

My fog lights will on occassion not work. I find wiggling or pushing on the relay will light them up. I think the relay socket may need cleaning. It could be you have a similar situation with your horn relay.