Bremmy,

Seriously, don't give your money away. It is SOOO easy. And I just did my first oil change the other day so I have very little mechanical knowledge.

The one near the windshield that is up a little higher is your Low Pass. This is the one you want. The high pass is near the radiator.

Low pass = pressures in
High pass = pressures out

The way you can tell is that when you start your car , turn on the AC full blast. Open your hood. The low pass line will feel very cold. This is because the refridgerant is flowing through the line (unless you have none or are low). The high pass line gets very hot.

It takes all of 10 seconds.......