Is the flex disc simply stuck to the yoke? Or have you separated the flex disc and the driveshaft still won't move? If it's the second, you can unbolt the center support from the body of the car and it will help it move even without loosening the drive shaft nuts.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

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