1. I recently spliced 5 LEDs into the existing lights that light up under my dash when i open the doors or turn on the dome light. I want to ...

1. I recently spliced 5 LEDs into the existing lights that light up under my dash when i open the doors or turn on the dome light. I want to know how many i can safely put in with out frying my truck

1. I also wanted to run more LEDs under my truck that light up when i open the door, i know i can tap power from the cig lighter/A/C power sockets but i don't know how to wire them to come on in sync with my MAP/DOME lights. Any help would be greatly appreciated

This is in a basic 2001 silverado