[Spridgets] Drilling a hole in the bodywork...

[Dave G.]

In order to get power to the license plate (tag) lamps, I am going to have to 
drill a 1/4" to3/8" hole through the rear valance - just to the right of center.

How can I do this without damaging my (very acceptable) paint job??

Will it work if I put Duct tape on the outer surface over where I want to drill 
and just drill bigger and bigger holes? Or will that damage the paint?

TIA
-
Dave G
'65 MKIII Sprite