In your case, you are better off just installing a bluetooth car kit with
its own speaker... All you will see is a button module... everything else is
Kits like this made by Sony/Erricson or Motorola can be obtained cheaply on
ebay... anywhere between $55 and up.
That website is interesting... but I got a feeling it will cost $3000 for
the system... we'll see, I put in a request.