I have used a JACOBS system, the car will need to be towed, to be stolen. It stopped my daughter (who had the key), she was so impressed she had me install one on her jeep. Bruce Roe
Actually, in the '50s GM had a universal key - primarily for repos. A friend managed to get one, and although it was stamped "do not copy", we copied it. I could start any GM car that had the old Briggs & Stratton keys.
