is this a clutch problem?

Hola amigos
85 camaro. 2.8L with a 5spd manual, 135k. Bought the car with the intentions of it being me get around vehicle... a gas sipper. I droppd a 2.8L with 75k on it and used the old tranny. I did buy/install clutch set (disc, pressure plate, and release bearing)
Now the problem didn't start untill it had been driven id say about 150 miles. When the car is in neutral somethings significantly rattlen' around. When i step on the clutch pedal or engage it into gear it's gone. I've been all under the vehicle makn sure starter and all mounts are tight. i don't have the shifter dust boot on so i can narrow the sound to behind the motor/infront of trans. What I believe to be the problem is the bolts holding the disc plate and the pressure plate to the fly wheel may be loose allowing the disc to wabble/rattle around. Does this seem sound? Some advice would be dope before i jump in and pull this sucker out again...the v6 motor and trans pull out together

sounds like the throw out bearing has a problem if its new it may need lubed pull the tranny and recheck your work