97 Driveshaft Vibration

[T-Time]

I've got a 97 Supercab with A/T with a noise coming from the rear end. I have rotated the tires, replaced the U-Joints , rear axle bearings and center drive shaft bearing. The truck was road tested after each repair. I now have a vibration coming from the drivshaft after changing the center shaft bearing. I know the alignment is somewhat critical however, I bought the part from NAPA and its not a direct replacement. Rather than messing with the alignment of the center bearing, I have read that Ford started using 1 piece drive shafts in 1998 to fit supercabs. I would like to replace the 2 piece original shaft with a 1 piece shaft. I have purchased a 2003 shaft from a junk yard that is the proper length. Has anyone done this conversion?

[big buck maniac]

as long as they are the same length it should fit right in