it's not so much "turning 6V into 12V", it's a matter of supplying the required amps, higher you step up the voltage the less amps you get .... depending on the rating it'd probably be fine for just a radio, but you wouldn't want to have it on when the truck wasn't running .... could just switch the truck to 12V - or you could use 2 batteries, one 6V for the main setup, with a 2nd 6V in series to give 12V for the radio, just take some creative wiring for charging both
Bill
