I put together an illustrated DIY tutorial for on how to build a 12 VDC to 6 VDC adjustable regulator circuit that will allow the use of your original 6 volt DC dash gauges to operate on a converted 6 volt to 12 volt system.
I was able to reduce the file and post it here as a PDF, click on it to down load. The resolution is not the best because of the file reduction, if you want a clearer version e-mail me.
