new engine with spec stage 3 twin disc install with SS clutch line and the chromolly clutch fork pivot ball Import parts pro sells. just got everything running and i can hardly get the car to go into gear without a lot of force, then when i put in gear with the vehicle off and clutch in the car started moving foreward while the engine was cranking over. it feels like the clutch must be partially engaged still WTF?

 

Take it back out and see what you or they did wrong. It happens...

The clutch plates are still engaged that's why it's pulling on you at startup with the clutch pedal to the floor.

 

Then again It might just be your clutch pedal needs to be readjusted.
Search Clutch pedal adjustment or google it with 350z at the end you will find it.
Trouble Shoot First Before You Pull The Transmission out.

 

Then take it back. Certainly the shop can adjust the engagement point.

 

Always happy to help. If you have other questions please do not hesitate to waste my time.