upgrade to factory rallye gage backlighting

Not sure, but iran mine on 6 volt, and 9 volt and the brightnesses dimmed to the corresponding voltages. These strips i have been told can be used with a rheostat for countertop backlighting so from this standpoint i cant see why not.

I agree, they should work and dim fine if the different batteries worked because all the rheostat does is vary the voltage.