A Radio in a 6 Volt Positive Ground

Is there a way to install a 12 car radio in a 6 volt positive ground car? I am restoring a 1954 Ford, The car is mostly stock, wireing batery type ect.  The customer basicaly wants a simple AM/FM radio and posibly a cd player.  If there is nota way to adapt a 12v radio , do they make 6v positive ground radios?Solartech Window Tinting and Electronics,contract installer

A dc-dc converter of appropriate rating (current/power). But you want one with isolated output - most have a common ground (ie, 0V or -ve). Otherwise a -6V to +12V converter so you can have a common ground. Most convert their vehicles to +12V, and negative ground. It's cheaper than keeping the 6V system.

I agree to convert the car to 12v neg ground. I was just exploring any options for positive ground audio. I know how to up the volts with a converter my main concern is the radio chassis shorting out with the cars +6vground dashboard. Hopefully I can convice the customer to upgrade the electrical system to 12v+ ground . Most of the wireing is frayed and the generator is not  working.Solartech Window Tinting and Electronics,contract installer

With an isolated output, a dc-dc converter is fine - ie, the radio's 0V (not +12V) is tied to the +6V chassis. That does mean 18V difference (or up to 21.6V if supplies were normal max dc battery voltage of +14.4 & -7.2V) between the two "hot" supplies should there ever be some bad interconnection, but speaker grounds are still ok (e, if speakers have one side to chassis instead of separate + & - feeds). But unless there is some overwhelming desire to keep it original with a 6V battery, I reckon the 12V conversion is better in the long run. IE - thinner power cables, easier and cheaper getting 12V stuff than 6V starters, coils, battery, lamps, headlamps, horns etc. The gauges should be relatively easy to keep at 6V, and if they are traditional but newer "heating" type meters (with "mechanical" bi-metal voltage regulator if used), their polarity does not matter. If they happen to be older coil type meters with permanent magnets, then the coils' polarity may (or should) need swapping. (If fully electro-magnetic it shouldn't matter - they are like wound stator and rotor dc motors - swap +ve & -ve and they still spin the same direction.) HOWEVER, maybe someone would like to sanity-check my sanity on that last paragraph. Else keep an eye out for my later corrective reply. (I am never wrong - except when I am.) A 6V regulator could be as simple as resistors (if gauge-current is reasonable constant, and I'd suggest 1 resistor per gauge in case one goes open), though maybe a ~6V regulator is better - find out the current required (per gauge or for the lot; 1A & 1.5A 6V & 8V regulators are common).    FYI - I haven't 6V converted, but my conversions from generators to alternators were well worthwhile. As to yet later conversion from external voltage-regulated alternators to the "all in one" alternator and regulator - well, I still can't stop raving about the advantages! (That was only a few years ago.) FYI2 - my "all in one" alternator interfaces simply to the existing generator wiring in my ute. The charge-lamp L-circuit (of D+) simply connects to the original charge-lamp from the old regulator. The S (Sense) wire goes straight to the battery +12V. [I don't use single-wire D+ type alternators - they can only sense the alternator's output rather than the battery which is what alternator voltage should be based on. Besides, you can easily increase the alternator voltage with an S-type - just insert a diode with the same voltage drop you want to boost by. And if the battery is in the boot/trunk - no worries - just extend the thin S-wire to its +12V; Sense wires usually take under 20mA.] If it's a 3-wire S&L with Ign terminal, then the Ign +12V just has to be +ve enough - it doesn't do the voltage sensing. [But if a 2-wire L&I (Ign) type, then the Ign +12V to it has to be close to the battery +12V. I learned the hard way - Ign +12V may not be near the battery +12V with lights & wipers and stop lights operating! I then used the Ign +12V to turn on a relay that connected battery +12V to the alternator's (regulator's) Ign terminal.] Sorry if the last confuses you, but it should cover all most alternator scenarios.... It's then just a case of finding a mechanically suitable alternator. [But I recommend 2-wire S&Ls, unless a simple single-wire D+ is okay (ie, no voltage drop between the alternator B/B+ output and the battery).]