That is an awesome story, Marc. That sign is amazing! You're LUCKY!
I found this sign years ago in a dumpster outside an old building that was being remodeled in Lincoln Nebraska, where I lived growing up. My Dad told me that Billy Wolff was a Harley/Cushman Scooter/Bicycle dealer in Lincoln. In fact there is a bike trail in Lincoln named after Billy. In the same dumpster there was an old wooden trunk full of WWI Army uniforms, they had gotten wet at some point and were rotten so I left them. Later I found out from an old time biker in Lincoln that Billy had been a motorcycle dispatch rider in the Army, hence the uniforms.
Enjoy, Marc