[Spridgets] Transistor Voltage Stabilizers on Ebay

[derf]

You can probably do the same thing with one of these:
ebay 290005253704	
if you can keep the current draw under 1 amp, which shouldn't be a
problem for a few gauges.
You can also get a 5 amp 10V regulator that will certainly do the job.
Vin goes to switched power
C goes to ground
Vout goes to gauges

Use a small screw and nut through the hole to mount it to something
metal or get a heat sink for it.  Those regulators lower voltage and
the by-product is a little heat.  I'm sure the $15 one has a small
heat sink inside.  For Spridget gauge apps, the heat involved would
probably be so little that you would only notice the heat sink getting
warm to the touch.

LM 7810 is a common 1 amp 10 volt regulator that you should be able to
find locally for a buck or two.  Radio Shack should have them although
Radio Shack is lately become cell phone and cheap electronics shack.
Cheers,
Derf