My friend had an old van with the same problem. He stuck a cow’s horn he just happened to have on the stub and drove it that way.
He also had one of those stupid yellow plastic waving hands in the back window, but he improved it by breaking off all but one finger.
That went well with the bumper sticker that said “I’m not as think as you stoned I am”. He had get rid of it off since the cops kept stopping him.
Fun times!
I had a bumper sticker an answer to “I brake for animals” bumper sticker. It said “i speed up to run down little animals”. Clipped it out of a National Lampoon. Got lots of nasty looks from little old ladies that don’t get satire. Might have caused me to get pulled over once or twice, also.