[ChiefM]

The connection is behind the bumper, you have to lay on the ground to unhook them.

I got the smoked ones because the truck is black.

I used these: Smoked LED Tail Lights for Cadillac Escalade / ESV 2007-2014 Assembly Rear Lamp | eBay
Here is the long 3rd brake light I used: Long Version Smoke LED 3rd Brake Lights Bar for 2007-2013 Suburban Tahoe Yukon | eBay

There is a picture of them installed on the Limo page you started.

 

[ChiefM]

Here is the page with the tail light conversion: ESV limo conversion

Here is the page with the 3rd brake light bar installed: ESV limo conversion