bunkwill

We have a 2007 Ford Edge SEL with the non-SYNc or navigation radio. We have already installed the Trip Tunes Advanced about a year ago. Now I purchased the Mobile Ease bluetooth kit for my wife. However, the dealer is saying I cannot have both installed at the same time. I know they use the same wiring harness that was purchased separately (and see where each has its own plug connector on the harness). But the dealer install guy is insisting both cannot be "plugged in" at the same time - I must pick which one I want to work. Can you verify that this is true? I would think it would have stated this somewhere in the description and/or specs of each of these accessories or at least with the harness that is needed for both. Then if this is the case - Does anyone know of a work around?