With this relay installed, the engine will turn over but will NOT START. In my haste a few times over the course of 13 years I have forgotten to click the relay and I know the engine just turns over just does not start. Also imho, any item that will allow the vehicle to run for a few moments will allow the vehicle to be moved out of a parking space to let them load it up on a flatbed. Your choice. I know my system works.
http://www.emergingent.com/vandalalert/vandal_alert_nostart_99f350ps_installation5.htm