I recently replaced the stereo system in my 85 3.25e, it shouldn't be that much different. getting the old stereo out is probably the hardest part, still, all you have to do is take off the glove box and the two panels above and to the left of it. Get it unscrewed, pull it out, then disconnect the wires. the slot is a standard size, your CD player should pop right in, and the wiring should be fairly basic. note- make sure you have the access code for your BMW radio if you plan to use it again.