does anyone think this could be done? found the sunroof Assembly cheap on ebay just wondering what else would go into it

 

Could it be done? technically probably. Would it be worth it? Probably not.
Besides cutting the roof, there is trimming the headliner and actually trying to make it look good, and drainage of the sunroof to address, just sounds like a headache to me. Along with your other post on the 2010 front end... You would probably be time and money ahead to just sell the 2008 and buy a 2010 with the sunroof if that's what you want...
In the past I would take on projects like this, but either I'm learning or getting lazy with age because I now think with major projects like that it would be easier to just buy what you're looking for