I'm posting the installation instructions, even though you can't fit them yet. That's because I will also use the photos when I email and PM each of you to discuss options for sorting out my error.
First a picture of the PCB (Printed Circuit Board)
as you have received it:
You can see there are three screw terminals, marked Ign, Gnd, and kbus (not in that order). You can connect anywhere you like, but there's a couple of places to consider. One is in the wheel well, but if you have a car that originally had a Mk3 then above the satnav unit is probably easier. Whichever, the connections are the same. If the car has had a Mk2 you can use the connection that used to go to the GPS receiver. Otherwise tap into the wires that go to the back of the radio on the right of the wheel well, or the wires that go into the back of the satnav module. Gnd is connected to the plain black wire, Ign is connected to the light green with white stripe wire. Kbus is connected to the white wire with red stripe and yellow dots. It's important not to connect the ign wire to a permanent live as it will stop your kbus going to sleep and flatten your battery.
I recommend putting a 1A fuse in line with the ignition wire.
Don't forget to put a hole in the side of the box and feed the wires through before connecting up. Once you have, you may forget which way the board goes in. Here's a photo showing you. It is tight, but it kept the box small, and it won't rattle!