I just changed all my bulbs to LEDs and it makes a world of difference. Check out J.A.'s write up on the LED swap for the interior lighting:
Toyota 4Runner Interior 5k LED Lighting Conversion
Even if you don't want to change them all out, it goes into great detail about the each bulb including the vanity's.
I still have my originals that I pulled out in case you don't want to go that route.