here is some info another member sent me, hope it helps.....
The front struts and spindles fit from the E-36, but you have to use the E-30 strut hats. You can use the E-30 lower control arms, with the E-30 M3 offset control arm bushings and machine 6mm out of the bushing brackets. This is done to center the front wheels in the wheel well. The E-36 M3 struts and spindles are the better ones to use because they use larger rotors and calipers. In the rear the 318ti, z3, and m-roadster trailing arms and spindles will bolt up. The m-roadster trailing arms are reinforced and come with larger calipers and rotors. The parking brake cables off your E-30 must be used because the E-36 models listed above are to short and won't reach the parking brake inside the car. With the E-36 M3 front struts and spindles you will need 17in. rims to clear the larger rotors and calipers. Hope that helps.
The Z3 and 318TI are the same as the E-30. It is however cheaper and easier to replace the trailing arms and spindles as one unit, then it is to order the spindles from the dealer remove the trailing arm assem., press the old spindles out, press the new spindles in, and then re-install the whole assembly again! Also if you read in my post i said the better trailing arms to run are the M-Roadster. These are the closest match to the E-36 M3 front suspension. The trailing arms are beefier ( re-inforced) to deal with the power of the M50 / M52 motor. Also they have bigger calipers similiar to those that the E-36 M3 runs on the rear suspension.