Well yeah it`ll protect the threads otherwise you need to get the bb tapped again. Just ask the guys your best option when i got my orange done i already had my disc mounts, headset faced so didnt want to do it again. The guy just put some masking tape over the surfaces, coated it then used a sharp blade to cut the taped sections off preserving the faced surfaces.
my frame cost 40 quid in bright orange, 15 for a fork in white.