That's definately helpful, thanks.

One more thing:
There is room on top of my current cassette deck, which appears to be room enough for a whole other unit. I was hoping I might fit the empeg there and not have to rip anything out.

True, I might not use the cd changer/cassette deck as often, but I'd like to leave them in and not rip up my dash for the sake of aesthetics. And if they're going to be in there, they might as well work