Not sure, I'm no expert BTW - but I've had a few tough lessons last week that may help!
The Porsche ones, is the PCD correct - 5x112? what size are they, eg 345x28? The offset is very important too, it can't be more than about 15mm.
I'd be surprised if you can make the Porker discs work. The easiest way might be to mate them to some R32 discs with custom carriers??