If your Burb is late model and came with factory "towing package" you likely
have "ready to wire" harness.
Just get the Prodigy and the harness for your truck and it's a 2 beer job!!
Google for the prodigy and check prices- they vary significantly but you should
be able to purchase it online for $120 maybe less.
Just hate to give the dealer $200 if you don't have to.
Knowledge is power!!
Here it is on Amazon.com with a harness for GM 2003 and up for $117 and
Home of the Louisville Slugger Bat!