Yet another big thank you for this post.
I did the install yesterday on a 2013 M3 following the directions in this great thread.
A couple of notes;
- Number 5 on the fuse block works fine for a 2013.
- When the A-pillar cover is removed, you can route the cable straight down to the side of the dash, without going all the way down into the side panel and come back up. There is a bundle of cables going down in there already. I used a big sturdy tie-wrap a a fish tool.
- I put my secondary display for the V1 between the steering column and the instrument panel . Using a big tie-wrap (the type used for airco ducts) as a fish tool I was able, with some patience, to push the cable all the way from the glove compartment to under the dash under the steering wheel.