There was one slight problem. US government rules at the time restricted the purchase of any vehicle that cost more than $750 ($10,455 in today's dollars). It was pretty obvious that they weren't going to get an armored car that cheap, and certainly not in less than a day.

One Secret Service agent was a quick thinker. The federal government did already have in its possession a car that just might fit the bill: Al Capone's, which had been sitting in a Treasury Department parking lot ever since it had been seized from the infamous mobster during the IRS' tax evasion suit years earlier.