OOPs, tried the bearing in the Center Support Collar and it is a loose fit. It should be a press in fit. You can actually move the bearing slightly within the collar. Called Old Buick Parts and they agreed the ones in stock are the same, they will now investigate why. Bought both the bearing and the collar from them thinking that would ensure they would fit together properly.
Any other source anyone knows of?
Not a good day at the driveshaft shop.