I'm looking at used Tahoes mainly because I can't afford a new one. I have found an 05 that has rear dvd and bose but not the nav unit. Can I put the factory navigation in after the fact and is it a simple plug and play install? Also, being new to Tahoes did the 05/06 models have a backup camera option? It would beal ideal if I could install the factory nav and then make a backup camera work with the nav. Thanks for the help!

Jerrod