Permanent Live Feed - Where?

[spasimodo]

I'm wiring up a dashcam, and want a permanent live feed so I can switch it on and off independently of ignition allowing me to leave it switched on when parked in supermarket car parks etc. I have connector to piggyback in the fusebox and the horn is live feed but appears only to be live at the fusebox when the circuit is completed.
Suggestions welcome.
Thanks Eric

 

[STEVE.M]

I'm wiring up a dashcam, and want a permanent live feed so I can switch it on and off independently of ignition allowing me to leave it switched on when parked in supermarket car parks etc. I have connector to piggyback in the fusebox and the horn is live feed but appears only to be live at the fusebox when the circuit is completed.
Suggestions welcome.
Thanks Eric

Interior light?

 

[White16valver]

Won't the clock also have a permanent live feed?

 

[JamesBryan]

Anything with a red wire is +12v before ignition.

Yellow is +12v after ignition. i.e. ignition live.