Craig, you beat me to it with your observation about the use of wheel chocks.  The parking ("emergency") brakes on most vintage cars that I've encountered are of dubious effectiveness at best, and a set of wheel chocks could save the day.  I'm from the flatlands of Florida, but I'll bet that most of out members (AACA) from the "Hills" already recognize the value of wheel chocks.   Chock 'em, Grog