go to your BMW parts dealer and have a look at the eletronic parts catalog,
you will notice that 318ti's & some Z3's run the same rear wheel bearings as the E30, therefore you should be able to use their drive flanges on the rear to go to 5 lug.
On the front do the E36 front suspension swap, I have also heard that E30 M3 hubs & bearings fit on the E30 spindles, can't confirm that though.
Let us know what you find