I've got a 92 with a 94 SC and TB, with a 2.3" pulley. To use that throttle body, you'll need a AFC calibrator. The rough running you are experiencing could be caused by poor airflow readings by the MAF. The unit from ZZPerformance works wonderfully.
You may just need a coupler to fix your blower. You can also get that from ZZP.
You should probably figure out which SC?TB?pulley combo you have. Measure the diameter of the pulley, see how thick the base of the SC is on the corner closest to the driver, where there is a bolt. If it is like two inches, its a 92/93 sc, 1 inch = 94/95 (I can't remember how thick it actually is, but close to those). Also, any possibbility that you can get the inner diameter of the throttle body? 96+ had the M90 sc that has a much longer snout on it. It is unlikely the previous owner managed to adapt one to your car.