Blu,
What do you have planned for the car? parades , shows, touring and cruises, or as a daily driver? Are you going to add accesories like a stereo, A/C, etc.? if you are going to enter it in VCCA shows and hope to advance in the VCCA classifications a six volt system is needed to keep from dropping too many points.
With the most expensive part of a 12 vdc system already installed it makes sense to me to go with 12 volts for daily driveing, tours and cruises from a practical standpoint, check for 12v bulbs, and you will need a good voltage dropping device for your fuel gage and other six volt items not being replaced.
12 volt starters, Generators, battery cables and regulators are usually less expensive to get replacements for unless you do the rebuilding your self.
There are articles on the internet about changeing to 12 volt systems, National Chevrolet Association in Minnasota catalog and you can order online at(
www.nationalchevyassoc.com ) , Patricks'(also online) Chevys of the 40s (online) in Arizona and other vendors sell kits and will help with the conversion. also the Stovebolt site has articles and advise, I would advise you to join VCCA application at (
www.vcca.org) and a local Region or club (Listed at vcca.org home page) link at the bottom of this page!
If you change back to six volts good heavy duty components and keeping the engine well tuned and a six volt system can serve you well.
I haven't seen any reason to change my '53 Belair over and I have bright lights and it starts well cold or hot.
I use a 12 volt booster battery set (compressor, trouble light, 2 12 volt outlets, a 300 watt 110 vac outlet, and 12 v battery booster) to run my CB and other 12 volt accesorys, it cost about $80 at Sams, and it is portable for airing up tires, blowing out gas lines, powering trailor wenches ,and trouble light etc., etc. and it can go from car to car.
It works well for me!