Bill was a dutch immigrant who took over a disused barracks building and converted it into a modern service station on the Hume Highway east of Yass. Bill died suddenly in the late 60's, and the operation was taken over by his son (also Bill).
The service station operated until the Yass bypass opened in 1994 and was demolished soon afterwards. I remember there was a large "Bills" sign in a rounded font, but can't find any photos of it.
The cache is located near the entrance on the Sydney side. Another unrelated cache is located on the Yass side exit.
Please cover well.