With the calipers from E36 325-328i (and a lot of E46, Z3 models) i offer a "small" 292x22mm brake and 5x120 solution, especially for the rims from BMW 5 and 7 series.
The flat 292x22mm Brake discs is modified and comes from a other car.
The caliper brackets need a little modification near the E30 Suspension.
Front: caliper bracket E36 325i or same from E46, Z3 .. BMW Part Nr. 34 10 6 758 104 (378)
caliper E36 325i or same from E46, Z3 usw. BMW Part Nr. 34 11 6 758 113 und 114 (54/22)
The most BMW 5x120 16 and 17 inch wheels will fit with this brake kit without distance plates.
ALPINA 8,5x17 ET13 from E32:
BBS RC 090 8x17 ET20:
E39 Styling 5 7,5x16 ET20:
On the rear you should make the 5x120 conversion with Z4 E85 hubs. Then you can mount a 272x10mm disc (modified from e36 325i rear) together with the E36 Compact / Z3 rear calipers.
... to the shop offers ...AnleitungenDescription 292x22mm brake update incl. 5x120 Umbau on E30 front with E36 325i SattelDescription 5x120 Conversion with Z4 hubs on E30 rear (www.e30.de) 
