I have a Saginaw 4 speed from a GM with the 10 tooth spline shaft, exedy 04049 oem clutch, and a bop bellhousing, all mated to a 76 455 with a science friction flywheel. with the car off I can shift into every gear just fine, but with the engine running it will not allow me to go into any gear with the clutch pressed to the floor. If i turn the car off, put it into gear then start the car with the clutch to the floor it act like a normal clutch and as I let out the clutch it will start to roll. but I can't shift out of gear without extreme force. I have adjusted the clutch many times, even over adjusting it to where the pedal wont go any further to the floor. the car does not roll at all when the engine is started with the clutch to the floor and in gear, so it feels like it is fully disengaging. I have also readjusted the linkage to make sure everything moves exactly how its supposed to without any binding. any thoughts would be appreciated.