Just one rail, one fitting and one check.
FSM says to hook up the gauge and key click on/off a bunch of times, but you don't start the car. Bleed the air out of the gauge. Then click the key about 10 more times and you should have 45-52 for a reading. Then leave the car alone for 10 minutes (key off) and read the gauge. It shouldn't go down more than say a couple of psi.
Personally, I've seen cars pass the key click test easily. I tend to like to get a driving test. That way you can see if the pump can actually keep up with the motors demand.