Being a driver of a street rod and going on several trips each year that require overnight lodging, this subject is brought up often in bench racing sessions. None of the above solutions work when the thieves don't even start the car to steal it. Their trick is to break into it, roll it out of it's parking spot, around a corner where they have parked an enclosed trailer. Push it into the trailer and it's gone. My idea is to design and build a brake line lock. If it can't move, they can't steal it. My search for an off the shelf line lock like you would see on a drag car or tow truck have been unsuccessful as they are unsuitable for this application. So please, if someone has already figured this type of anti-thief device out, jump in here and let us know how you did it. Thanks