You can do either (1) or (3) yourself if you are handy and willing...there's a sticky thread at the top of this forum discussion area that discusses installation of the MY18 head unit in MY14+ vehicles as well as other threads. For aftermarket, at least for seeing what's needed, Crutchfield is a good site to explore as they have both the head units that are compatible as well as the necessary and required interface kits to preserve vehicle functions, such as steering wheel controls and backup cameras.