I want to return my 1914 runabout to the original bulb horn, but have no original parts to go by. What is the correct length horn set-up to order? I tried to get an idea of the length by holding a piece of rope between the firewall and where I think the bulb bracket should attach. Two feet seems a bit of a tight stretch, but at three feet there seems like too much slack.

I just measured two originals that I have. One is 20", and the other is 19 5/8". This is without the reed housing installed.