If you've got some kit that still requires 6v to work I can sort you out with circuit diagrams and parts lists for a 12v to 6v convertor that is stable and does the job way better than one of those empi resistors that you can fry an egg on! It's simple enough that you can build it on a bread board if you don't have a PCB etching tank. And small enough to fit in a box just larger than 2 matchboxes stuck one on top of each other. The only thing that governs it size is the heatsink.