I need a backup power source off/near the fuse box that only comes on in reverse (07 FX4) for auxiliary backup light, camera equipment, proximity sensors, etc. Can you help? I'd rather not tap the lead going to the rear bulb if I can help it.
Thanks!

 

for something by the fuse block use one of these https://www.google.com/search?q=tap+...w=1280&bih=707

 

I'ld run a seperate fused power wire through a relay and back to where I needed power, switch the relay with the BU lights. Use 14 or 12 gage wire on the main circuit, fuse near the battery with a 20 (25 ok if using 12 gage the whole way) amp fuse, and use a 30 amp relay available at any auto parts. The switching wire and relay ground can be 18 gage. Take this circuit to a terminal point. Then fuse each accessory seperately according to their need from there.