Pelicanparts website has a DIY with pics.
Hope you're a small person. It took me a while to do this because I'm a 6' 210# guy. But I got it done. Be careful not to pull out the plastic heat ducting because it's a real pain to get back in correctly. Otherwise this is an easy job.
Expect to break out the old switch. Also, getting in the new switch was a bitch. I had to shave a little off of the new switch to get it in. It's been in for 10K, no problems.
98 328i, black/black, manual, canadian sport pkg, ECIS intake, koni sport adj's, dinan springs, oe/oem clears.
Considering: tms shark,M 17" wheels, larger sway bars.