Just throwing the idea out there. Could it be done? I saw with that RS prototype AM was able to squeeze a V12 in the frame. The car seems to be selling well. I think it's the best looking new car under $150k. If someone like Heffner could make a $20-30k turbo kit that might be a nice volume product for the aftermarket.
Heffner would build one for you, He would build a turbo minivan if he thought he could sell it. He seems like a great tuner/builder. Im sure theres enough room for it under the hood.