I found this info: 1953 was the changeover year for Buick from 6 to 12 volts, and all models except the Special have 12 volt systems from then on. Only the Special continued with the straight 8 engine and a 6 volt electrical system into 1953 - all the V8 Buicks had 12 volt systems. http://en.allexperts.com/q/Cl***ic-Antique-Car-2542/2008/1/dead-battery-53-Buick-1.htm
Sorry, but that factory literature is wrong. Buick (for the V8), Olds and Cadillac went to 12 volts in 1953...Pontiac and Chevrolet in 1955, Ford and Chrysler in 1956. Frank
You are too quick for me. I immediately realized my mistake and deleted my post, and added the correct info with a reference. Sorry for the screwup.