1. Purchase a set of green color filters that fit your Lexus RX300 blue. You can find these online or at some auto parts stores.
2. Remove the dashboard bezels and trim pieces to access the dashboard lights.
3. Place the green color filters over the dashboard lights and buttons.
4. Reinstall the bezels and trim pieces.
5. Turn on the dashboard lights to see the new green color.
Please note that this modification may not be reversible, and it may affect the warranty on your vehicle. It's always a good idea to consult with a professional before making any changes to your car's electrical system.