Decide where you would like to mount the equalizer. Connecting to the tape monitor channels will require connection to only your receiver. If you cannot find a black wire on the receiver, remove a bolt near the equalizer mounting location and scrape away any paint covering the location around the bolt. Some vehicles will have space for this in their dash.
If you have more than one set of speakers, you could use both, but if you did, then the speakers from the receiver would have unequal sound.