I also have the aluminum part powdercoated but it does not contain bushings.
I ended up selling someone what I thought was an NA diff for his miata, turns out its a t2 and I dont need a turbo rear end and neither does he so I'm trying to hold up my end of the deal here.
Located near Detroit currently, only looking for LSD models. NO open or welded diffs!
I might be interested in 2 S4 NA FC differentials...