Everyone who responded to my post, thank you!
I made an appointment with the MB dealership to get my computer reset. Yes, I had someone other than Mercedes perform the install. The dealership refused to install such springs for some reason, telling me that the SLK's frame wasn't strong enough to support lowering springs, or something like that.
Does anyone know how long / how hard it is to reset the ABS computer in my '00 SLK? Is it something that can be done in one day or an hour or something? If it's something like a regular computer, I would assume it wouldn't take that long, just plug in and hit reset or something, am I right?
Thanks for all your replies!