GRINDING NOISE, please help!

[playastarkz123]

Ok me an my father just completed dropping an s13 sr20 motor in my 240sx. After driving around a little bit we noticed a strange grinding noise, almost like when you try and shift without pressing the clutch in all the way. We only here the noise occasionally though and only when going to into first gear or reverse. We also hear the noise slightly as idle sometimes but when u press in the clutch the noise goes away. What could this be? We know nothing is wrong with the gearbox because after the swap we got the car tuned and dyno and we out the gearbox through hell, this also eliminates the guess that there was a problem with the motor. My dad thinks that it could be the Throw out bearing but i just wanted to see what people on this board think. The TO bearing was working fine before the new sr install so i dont know why all of sudden something would happen to it.

Anyone know what this could be?

[playastarkz123]

no one has an idea?