Use an "Add-a-Circuit" (fuse tap) for a clean install. Note that this is often a 3-pin fuse slot, so you may need a specialized mini add-a-fuse.
This requires a bit more navigation than the fuse box. 3. Ignition Switch Harness
Here are the best, verified locations to find ignition-switched power on your '04 Silverado. 1. The Best Spot: Passenger Side Fuse Panel (F26)
For clean, safe tapping into the fuse box.
Use a multimeter or test light to confirm it is hot only when the key is on. Essential Tools for the Job
Fuse #26 (10A) —labelled as TRL B/U, SEO, or "Special Equipment" / USB.
What are you trying to power (e.g., dashcam, CB radio)? Are you comfortable using a multimeter to verify the power? looking for accessory switched power