Last week I went and checked the bulbs for the cargo and 3rd brake light. When I pulled out the stock lens there was no bulb base retainer in place.  Luckily the wiring was still intact. 

I ordered a LED replacement kit and it arrived today. This kit will serve as a cargo light as well as the 3rd brake light when brakes are applied. Everthing worked out as planned, the cargo light activates when either the interior light switch is set on or the driver door is in the open position.