Update.
I installed mine, pics attached.
View attachment 191704
View attachment 191705
For power sources:
(see fuse panel chart on page 6-11 of 2000 Protege manual)
Ignition-on wire: used position 7 in the fuse panel, just inserted the wire with the fuse.
Always-on wire: I attached a spade connector to the wire, then connected to the LEFT side blade in the unmarked spot above position 16.
Easy. Works great.
I no longer own the car so I'm going off memory. I'm not sure that both wires associated with the fake alarm are shown in that pic. The "black square" you are referring to is a Add-A-Circuit fuse tap which I think is the power source for other projects- I added two extra 12V power ports, and I added a auto-dimming compass mirror, but I forget the sequence in time and exactly what I did. Sorry that I can't confirm the wiring. Helps to have a multi-meter to test the various open fuse positions.