As for reverse engineering--since when is it illegal to open the hood of a car _you_ bought and figure out how it works?
Since the Federal gubbernment required all cars to have airbags which can't be shut off.
Since the EPA required that all cars idle at a certain speed and not be adjustable.
Since OBD2 was required that is not compatable with any off-the-shelf computer interface devices.
Things are worse than you had thought. =( www.lp.org