Not all cars are that way or alarms, that is what DEI calls D2D. Where the alarm wires connect to a special all in one bypass module (even has no key required to operate) and only one wire from the special module goes to a wire on the OBDII port on the car.
If you really want to install this yourself I can help you, but to be completely honest, you should have a professional do this whether at mom-pop shop or take it to Best Buy. You don't wanna get cheap on this upgrade or any for that matter. You will run the risk of the alarm going bad since it isn't that great, (Things like one day the car won't start with a key or the doors don't lock, or the sensors go bad) if the price difference between that and a Viper was only ten bucks why didn't you get the better known brand? Did you buy from sonicelectronix? They have Viper too you know.
DEI FTW!!!!