M3 differential

[rrrs]

I have a possibility to buy locally 188 medium size differential from 1999 M3 automatic with just 70K miles.
It should be LSD with 3.38 ratio.
Could someone please confirm if this would be a bolt-on for 1985 E24 as long as i replace rear cower with mine?
Should locking function still work well after 70K miles or would I have to count on rebuilding it?

[Brucey]

I think it will fit with a replacement rear cover, but others will know for sure.

70k motorway miles won't have worn the LSD at all. But a tenth of this mileage 'driven enthusiastically' on twisty roads could have knackered it. I've been surprised in both directions.

cheers

[rrrs]

Thanks a lot for your comment!
Any way to test if and how worn is the LSD?