I doubt that the LCI "xenon" style tails will work on +12 halogen equipped cars. They probably need to have the headlight switch changed out in order for them to work properly. I would guess that the reason the 08-11 cars can accept the 12+ lights is because they already have LED tails from the factory. I'll be finding out soon enough because I'm working to borrowing a set of 08-11 tails from someone who upgraded to the +12 style, and try them out on my car.
Here is a photo of the +12 style "halogen" tails on my car (Yes, I know it's dirty):