Of all the roadsters I've ever worked on, none have had horns. It just isn't a priority, just like turn signals.
But since I had all the parts, why not?
Actually, I thought I had all the parts. I couldn't find the vintage column mounted button, it's somewhere in the garage. No worries --I'll be using this old cigar lighter, and it makes for good camouflage too.
All told, I have to have only $10 in swap meet parts here. The lighter being the priciest part at $6.
You know that lighters lock down while the element heats up, then pops up when ready. So to prevent that, I bent the three inside prongs enough to only make a ground contact and no more. If the lighter were to lock in, the horn would blare!
A little paint, and it looks new again. I also made the missing top part of the dash holder clamp, it's what will hold and ground it to the metal dash.
The next problem was where to mount the horn. Space is limited, plus horns aren't pretty to look at.
I though of putting it behind the engine and under the passenger's feet.
Then I found that there was space under the radiator and behind the front grill. This was only better because I don't want to be too close as I toot my own horn!
...also, more hidden.
There was nothing to bolt it to. So I made a simple strap from steel flat rod that bolts under the radiator mounting bolts.
Finally, wiring it all up. A horn relay is important because without it you be sending the full power of the battery through the switch and for some reason that is bad. That is why they make this relay.
As this diagram shows (taken from my basic hot rod wiring post), battery power comes from the fuse block to the 'B' post on the relay. 'H' is connected to the horn, 'S' goes to the switch.
A 20 amp fuse should be fine.
Here is the relay mounted under the steering column bracket, nicely hidden from view.
The lighter looks right at home on the dash of a 50s vintage car. I've been told everyone smoked back then!
Today, this lighter has become an "anti-smoking" scare tactic. An unsuspecting smoker will push in this lighter only to get a warning signal! In Your Face!