At the above link, you can find the 132 page NC inspections manual. Page 41 covers lights. It does not appear that simply having a hole drilled in a headlight housing would lead to a disapproval. I do not believe a cleanly drilled hole rises to the only seemingly applicable disqualification, which is "(c) Any lens is cracked, broken,..."
19A NCAC 03D .0533 LIGHTS
1. Headlights shall not be approved if:
(a) There are not at least two head lamps (at least four on dual
head lamp systems which require four units) on all
self-propelled vehicles except motorcycles and motor driven
cycles need only one.
(b) The lens produces other than a white or yellow light.
(c) Any lens is cracked, broken, discolored, missing, or rotated away
from the proper position, or any reflector is not clean and bright.
(d) The high beam low beam dimmer switch does not operate properly
or the high beam indicator light does not burn on vehicles
manufactured after January 1, 1956.
(e) Lights can be moved easily by hand, due to a broken fender or loose
support, or if the mounting does not make a good ground.
(f) Foreign materials (such as shields, half of lens painted, brush
guards, etc.) are placed on the head lamp lens that interferes with
light beam of lamp.
(g) Lights are improperly aimed using an approved light-testing device.
(h) Lights project a dazzling or glaring light when on low beam.
(i) Mechanical/wall chart aimer tolerance range is 4 inches up, down,
left, and right. On board aimers tolerance is 8 degrees up, down, left
and right. Optical aimers are either go or no go.