Chevy s-10 add on

It sounds easy but I dont think the factory system can hold options. Even diode isolating it from the other components. As for the factory alarm, it will only sound if the door is opened. If someone breaks the window it will not go off. All they would have to do is break a window and unlock the door. By doing that the alarm will never sound. Even by adding your aditional options to the factory alarm (if possible) the "theif" would just have to unlock a door to disarm the alarm. This could take a whole 2 seconds and all it would sound like is someone beeping the horn. With the aftermarket alarm you could add on as may options as you would like i.e. glass break sensors, remote start, shock sensors, pin switches, magnetic switches, proxsimity sensorsand up to 1000+ft range and an led to "prewarn the theif" just as an example. When any of these zones are triggered the alarm sounds and there is no way to turn it off unless it gets disarmed by the remote. Here is a better way to think about it. It sounds like you may have had a problem with people stealing your radio. If it stops them once it has already paid for itself. And now the theif knows about the alarm and 99.9% chance he will not make another attempt.

But if you still want to add these components to your exisiting alarm, go for it! If it will work or not I cant be the one to tell you but its worth a shot. 

That sound about right. Give it a try.

Here is your wire:

Go to your local mobil electronics dealer, they should be able to get you the parts your looking for.