After studying carefully Seanhump's thread (http://www.slkworld.com/general-mod...erwise-know-i-like-challenge-now-then%85.html) and taking care some useful advice of my good friend Gogos(member nickname) who has already made the project with the r172 steering wheel too, i took the risk buying from an eBay seller the new style steering from the latest models. It comes from a W205 with amg package and it is flat bottomed with perforated leather parts in the steering rim and leather airbag. Fortunately, its dimensions are very familiar with those of r172 steering.
Firstly, i gave the new steering's buttons to a friend of mine who is electronic engineer and asked him if he could make them work with the r171 steering's SCM. He both "decoded" the old r171 SCM and new steering's button PCBs and made them work together using new harnesses and connectors for the buttons PCB. He didnt make any modifications to the old r171 SCMs harness. He also use connectors for the wiring of the new airbag. All functions work perfectly!
Following the success of the first part, i had to lathed the new central axle in order to mount to my old steering angle sensor.
It took me many hours thinking how to fit the old r171 SCM (very very big) to the new steering which has very little space inside. The only solution was to put it vertically because of the airbag plate's screws. I had to cut a small useless piece of the r171 SCM and make a small slit to the steering due to lack of space (Nobody will notice anything after the leather warping).
I removed and sold the shift paddles of the new steering because i have manual gearbox and i made custom plexiglass caps to cover the gaps.
Furthermore, i had to find something to cover the small part of the steering angle which is visible if you try the new style steering.
So i found....the transparent cover of a 10piece disc holder! Okay, it looks funny but it mounts like it was designed for this project! Precised height and diameter. I couldn't believe it. I made the necessary holes.
Finally i wrap the "funny plate" and the steering's back with leather in order to cover the plexiglass caps and the small overhanged part of the SCM at the bottom!
I have just updated the photo uploading via another hosting because they were not visible to all PCs.
I will start a separated topic for the interior of my car in a few hours and i will post it here.
Thank you for this post spi89!
I've bought the same wheel to replace it in my 2011 SLK350.
Do you have some details about the electronic engineer tasks that you mentioned? I'm lost there (This is in order to make it work with the original wheel connector). Thank you from Argentina