At about 37 minutes the Triumph roadster Cindy Adams (Anne Randall) is driving has a license 247 PCE. This is the very same license that was on the Chevy Nova used in "The Manhunters" earlier in the series.
At the 40 minute point, the license on the black Chevy Caprice is 825 DQI which is exactly the same as the one on the Lincoln Mark IV in the series "Cannon".
It's never explained how Olson's henchman Jack sabotaged the illusion. Tony says that the padlock was jammed. However, the illusion is in clear view on stage the entire time. The only time it is covered by a curtain is when Laurie is inside the tank, but she never sees anything unusual.