LSD install info needed.

[Dr3K0]

Hi guys, I have been out of the forums for a long time. Mostly by work and duties but also cuz I lost half of my license points in 1 year r: So I parked the 1 on the garage and put a cover until its time to get back to it. Now the time is here and I have collected a lot of parts during this time. Mostly will be traction and suspension. I want to clear some question before I can start.

1.
I sourced a 2007 MT rear differential to use for my LSD install (ring gear). This differential has around 100k miles. My question is should I use this 100k differential or use the one from my 09 135i (18k miles)? Mainly due to the bearing wear, if any.

2.
In the subframe bushings, the front one are installed from the top and the rears from the bottom?

3a.
I know there is needed a special 50mm wrench to loose a nut on the differential. I feel stupid to ask this but, how is the process to actually loose the nut? Seems very straight forward but the nut on the sourced differential it just spins and does not go anywhere.

3b.
Also can someone explain me how this nut function is?

4.
Where I can find the LSD install info specs like torq specs, backslash info and such.


Thanks in advance

Dr3K0