The empeg also has an aux input, and you may well be better off connecting your existing head into it rather than vice versa. You will then be able to take advantage of the empeg 20 band paramatric equaliser when playing CD's on your existing head.

Connecting it the other way (empeg into your Panasonic) maybe be easier to wire, though, especially if you don't currently use external amplifiers.

Whichever option you go for, you'll need the physical space to fit a second DIN head unit.

Rob