clutch fork problems

I have a 74 Dart sport, 360 magnum with carb conversion. I have a Tremec 5 speed conversion that came with a dual disc clutch & the Lakewood style scatter shield. I did away with the duel disk system and just went with a standard clutch setup. Now my clutchscatter shield scatter shield fork opening before it can engage the throwout bearing to the pressure plate. I don't know what's wrong. anybody else ever had this problem?