Which 3 series were they on? Some 3 series rims will require a 15mm spacer, some a 20mm spacer, and some a 25mm spacer. All depends on which 3 series they cam off of.
To make the offset right you're going to need at least a 15mm spacer to get them out far enough. That length of spacer is going to require longer lugs as well. Checking TMS and I see that it'll cost $270 for a set of 15mm spacers and all new 15mm longer lugs.
And something tells me that even if you went to all of that trouble you'd probably at least have to roll your fenders. And I'd bet that still wouldn't be enough.
E34's don't do well with 19"s in either fitment or ride/handling/performance. And E32's are virtually identical to E34's suspension-wise. I'd not imagine they'd work real well on an E32.
I personally wouldn't touch them. Offset is way wrong. 19" tires aren't cheap. And E32's weren't meant to deal with 19" rims.
But if you really, really, really loved those rims, felt like taking the risk of going to a lot of hassle and expense trying to get them to fit (which they might not depending upon how different the offset is) and wouldn't mind the horrible ride/handling and didn't mind risking blowing out the tires due to not having enough sidewall then go for it.
Cosmos Black/Black 1995 540iA M-Sport
BMW Individual Exclusive Edition, 1 of 65 total, 9/25/95 Build