I have an 05 TB LS and I want to put the factory nav unit in it. It does not have the bose radio. I only want the factory I do not want any aftermarket. What one do I buy? How hard is it? Any help would be great.

Your best bet would to go on ebay for this. There are a couple of guys who are selling them because they have the aftermarket ones. Find out if they have the CD included with the radio. Here is a start:

http://cgi.ebay.com/ebaymotors/GM-HUMMER-H2-DENALI-TRAILBLAZER-TAHOE-NAVIGATION-RADIO_W0QQcmdZViewItemQQcategoryZ38653QQitemZ22009 3818069QQrdZ1QQsspagenameZWD1V