dei 562t into 90 300zx and 03 rav4

Im getting a good deal on a pair of 562t remote start/alarm systems, and im planning to install one in my 1990 nissan 300zx and the other in my girlfriends 2003 toyota rav4. I know that the rav 4 has an imobilizer key, and I have to add a doorlock actuator to the drivers door of my 300, but barring that are there any issues that I should be aware of before jumping into the project? 

Reading through this site should provide you with all of the information you could possibly need to assist you in your project. I recommend soldering all connections and taking your time. If you run into any complications, just head back on here and search, if you do not find your question already answered, post it and I am sure someone will be able to offer some assistance.Installer, IT support, and FFL. I need less hobbies.

I have just finnished putting in two of these so if you have any problems just post them here.

The only thing that I am concerned with is the ability of the system to provide a decent amount of security for my z, as it would be pretty easy to steal.