01 cassette player issues

[vietec]

Hey guys, my sister did a coffee spit-take on my cassette player (was her car at the time) and took it to a dealership to clean. Well...she must've pissed someone off, because the cassette door was broken, and the unit wasn't really cleaned. Beyond all of this, the cassette player itself didn't work, as well as a few buttons (I expected the buttons to not work, after the coffee). Well, now that I own the car, I am trying to fix this particular issue. I bought another head unit from ebay, but I am having issues with the transplant. The guy said that he took out some kind of antenna unit, and that all I would need to do is transplant my old one over. Well, I'm having trouble finding out how it'll work, so here's a picture of my old unit:
http://i119.photobucket.com/albums/o158/vietec/BMW%20Radio/DSC01052.jpg
Here's a picture of the new unit:
http://i119.photobucket.com/albums/o158/vietec/BMW%20Radio/DSC01051.jpg
Here's a picture of the two together:
http://i119.photobucket.com/albums/o158/vietec/BMW%20Radio/DSC01049.jpg

So anyone know how I can get this new unit to work in my car, or get the old unit to work completely again? Thanks!