I'm assuming you're referring to the antenna? Yeah, I do realize the antenna will be an addition since the HU that came with it, doesn't have nav; however, I'm not sure what all that entails or how difficult that will prove to be.

I think I can run down a used unit with little problem, but I want to make sure I buy one that will work and work seamlessly. For that, I'm willing to pay. I just don't want to pay for something less than that.

Surely there's a list somewhere of models that will work with "x" vehicle outfitted with "x" options