Which circuit in pass side fuse panel to use for ambient lighting?

[IA-SteveB]

2002 Lincoln LSE.
I have some LED ambient light strips that I want to hook to a fuse tap to get power only when the headlights are on. I tried using #9 for the right side low beam, but it is constant power. Is there a better fuse choice for switched power when the lights are on? I was thinking #33 for switch backlighting.

 

[joegr]

2002 Lincoln LSE.
I have some LED ambient light strips that I want to hook to a fuse tap to get power only when the headlights are on. I tried using #9 for the right side low beam, but it is constant power. Is there a better fuse choice for switched power when the lights are on? I was thinking #33 for switch backlighting.

There is no switched positive power for the headlights. You would need to add a relay. The ground side of the headlight bulbs is switched on or off to turn the headlights on or off.