I have a 3.46 MED case LSD that I paid through the nose for when I first bought the shell that I won't be using, but intend for it's sale to fund the 210mm conversion. I also have a few other ratios in med case opens, 3.64 and 3.15
I have a modified E23 (I think) crossmember that I've welded the large case diff carrier to. It lookes twice as strong as a std E30/E36 compact crossmember. I'm trying to decide how to do the rear mounts now as I'll need to push the rear diff mount channel backwards to be able to get the sway bar back in. Large case occupies the same space as the swap bar.
I have E23/28/32/34 rear arms, with the upper shock mount - bolt on 'large' (930 compatible) CV's and the large case 3.15 or 3.64 diff. The large CV's have been coping abuse on the 7 for years now with a reasonably sharp shift kit fitted, so they'll cope with 750kgs less to push around.
I should be able to use E28 half shafts but thinking I'll go straight to 930 CV's and an off the shelf A/M shafts if I can find one the right size.