Sorry but i have to chuckle at 'rugular'...i promise i'll make it up to you with helpful information.
The three leads that go to the opus are red, black, and yellow. You should connect the black one to chassis ground (so any bolt in your car that is well grounded...anything into the frame should work), connect the red one straight to the battery, and connect the yellow one to something that has 12V only when the car is on. Is the 12V power supply in the trunk switched? If not, you should find one that is and use that to connect your yellow wire to.