Sorry to bring up a serious question on a Friday...

I am installing two small 12v fans in my 83 Westy, one on the dash and one on
the side of the closet to blow down on the bed. Is there an easy place to tap
into the secondary battery wiring harness from each of those locations? (I don't
want to run down my starting battery.)  It looks like the light over the sink is
wired into the main lighting circuit (replacing the dome light?) so that would
not be a great choice.  There is a bundle of wires in the cupboard below the
sink going towards the refrigerator and who knows where else...

any hints would be greatly appreciated.

Dave Richoux