Yeah. Don't just pull it off. Again, if possible, try to track down the installer. From what I have seen on the E36 wiring diagrams, though, there really isn't much they could have done. If you don't feel comfortable cutting and soldering wires blindly, take some pictures of the wires that go into the module an tell us where they come from. I do embedded electronic control engineering for a living, so I may be able to help remotely.