I tried searching but could not find any answers. My car came with the Premium II package which is pre-wired for bluetooth but I don't have a contact plate. Should this have been installed or is it an extra add on?

Thanks

 

Talked to my dealer - $1741 for parts plus installation. Basically "prewire" means it has a wire - nothing else.

 

Correct. It's been discussed many times before. Check SLKWorld.com for several threads will all the information available.