You probably have the bellhousing to fit the clark transmission. Here is an old trick to use the stock 302 pressure plate with the 228 bellhousing: Put the pressure plate on a drill press and use the chuck and a spare throwout bearing to press the diaphragm down as if you were disengaging the clutch. Put washers between the diaphragm and the pressure plate housing to keep it compressed. Install clutch and tranny, remove washers. It worked when installing my 302. You also should be able to do a minimal amount of grinding to make the pressure plate fit without doing the washer trick.
