converting cargo light to 3rd brake?

[cleansquare]

My truck doesn't have the cargo light but I've heard of others installing one. I think I could buy one from lmc or somewhere.

Has anyone ever converted them to a third brake light?

I figured if I could candy the clear lens cover red, and get the right bulb in it, couldn't you just run a wire to the rear of the truck and hook it to the taillights?

It wouldn't be a cargo lamp anymore just a brake light.

Ive heard from others who have added a newer third brake lamp from a different car like a nissan...but I want it to look factory.

Any ideas? I've also read some bring it to the white wire by the pedal..