how to reduce 12v to 6?

Hello, Sorry I don't have a basic understanding of electronics, but this is probably an easy answer.... I want to run some Xmas lights ( on my car) off some caped off wires that used to run 12v driving lights. The led string lights I have are designed to run off 2 C batteries. I believe they are wired in serries. I want to run 2 strings together. Does that require 6 V? (1.5 V x 4) Can I put in a resistor in the + line to reduce it? Or might these LEDs run ok on 12V? They only cost $2.79/ string, so not a lot invested. I know I could keep the battery packs, but would prefer to run them off an existing switch . Thanks for any direction.   Scott

Yes you can do it with a couple of resisters. You'll build what's called a voltage divider. Here's the basics, with a calculator: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/voldiv.htmlSupport the12volt.com

Forget the voltage divider. Find out their current and use the normal R=V/I formula, eg - try    LED calculator (Source = 12V or 14V, LED = 6V, current = ?ma (20, 40, 100?).