The chassis checks appear to be different from and unrelated to the cracking of the upper chassis rails at the upper wishbone rear mounting brackets that led to the bolt-on brace a couple of years ago for pre-2014 chassis or indeed, new chassis for those of us that have experienced the cracking of the 2012 and 2013 chassis.
Got it. My car is from 2014 so I thought I was safe regarding the chassis problems but this "recall" is for all cars up to (and including) December 2014, so my car is within the time frame concerned.
I have no idea what (and where) I should be looking for. Called the dealer, he doesn't know either but he told me he was going to ask the factory for more details
Have no "M3W" pedals so that doesn't concern me
My car was the first to have the lower wishbone crack discovered, the picture below shows the crack propagating from the weld.