i don't know about the wattage, but i've seen some of those aftermarket "bright-white" bulbs that really improve on the lighting on the interior.
i have a mini-neon stick, about the size of a Tetra-Pak straw that a friend made, and it's really bright. well, at least it was in my Jetta, i wish the Corolla dome was more 'centre.' i might add one i got from another gt-s closer to the windshield.
i might also add some lights in the doors, so when you open them at night, you can see, like a sedan
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