whooops ... yea i meant ap8 ... gotten confused with the tow mirror upgrade and this ... I'm a bit unsure on the two ways because ... ever since I programmed my truck with my edge evolution programmer onstar has been unable to read my tpms or any of the other things it checks, just gives errors. So, I don't know if the two ways would work with my situation ... going to have to look into it a little more. Anyways just wondering how the two way works and find out what would be best ... also to see if the dealership charges an install fee.