[Newlin]

Which alpine HU would you recommend then in the 100-200 dollar category for powering the four speakers?

I haven't decided yet on the speakers, I have been looking at the alpine s series as well and I figured I can deal with fitting in a 6.5 in the door for the added sound.

Is the gm antenna adapter something I can find pretty easy online?

I think I'd like to grab the head unit first so I only have to wire the antenna and everything at once unless you guys recommend differently.