An actual billboard, or just a taste of what they'd look like if old man Johnson shook loose some shekels for roadside ads? C'mon, he's got 200 towns sewed up tight, why not live a little?

To which old man Johnson might reply: he didn't get to serve 200 towns by spending extra money on foolish pictures.

The billboards of the era always had that latticework on the bottom. Probably wood. Probably rotted after a while. Unlike the billboards of today, they were on the ground at eye level; motorists of the bygone era would wonder why we had to put them up on poles. (I presume it's so they're seen for longer periods of time.)