How do you change Toyota Celica dashboard lights?

Sorry, this won't answer your question but maybe point you in a direction.

Also, I have no personal experience with this, but it might save you some time searching to find this same information. This is not all inclusive, and there may be better ways to do it.

For changing the actual bulbs behind the dash, you remove part of the dash and replace the bulbs.There are other sites that can give a more in depth look at the process.

For changing the hue/color of the lights the color is most times determined by pieces of colored plastic actually glued into the dash itself, being backlit by a regular white light. So this may be more challenging then it seems. If you mean the lights in the guages, you still have to remove parts of the dash itself but on some cars, I cannot tell you which, you may be able to change the color by removing a colored plastic piece and replacing it.