Impossible with the current engine code.
I believe Kaje is working on a new kind of buildable-brick car script and model, I was just on his server and i tried to get it working. So far, it works pretty well. next time you see him, ask him to release or just play around with his new car. Besides, it would be kind of cool to have a car with you in the front, and built on the back a huge Shoop Mah Woop thing. Also, on the truck there needs to be a -built-in brick, or else it's like building on the top of a magic carpet. It wont work.
O o
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