so I need to get my diff rebuilt, and maybe upgraded I have been looking on here to find a few reviews / options and can not find a conclusive answer on who to use! Some people say X company is great, others say they were terrible! Others say use this company, you ring them up and then they say they don't do M3 diffs and cant get the parts anymore! so... to finally get some names Can people who have had their diff rebuilt and had good experience list the supplier below, and also if its bad! thanks!