I found out there's an archive of every issue of the magazine, but I'll stick to the issues I have.
All are from #66, April 1966
Avis Rent-a-Car had the campaign “We're number two and still trying harder”
26 Honest Attempts That Resulted in Laughable Failure - The successes of the world are propped up on a hulking heap of failure. So grab your failure shovels and get at that heap.
27 minutes ago