Now set your beer down and reinstall the spring and pins.
Hammer the lower pin into place, and slide the lower end of the spring behind it. Next, depress the upper end of the spring with your hand to keep the tension off the upper pin until you work it into the hole on the outboard side of the caliper.
Once it's in the hole, hammer it until you detect a change in the sound from the hammer (this is how you know it's properly seated).
"If it's too loud...well, you know the rest."