Studied MB & Haynes manuals & previous posts advice on how to remove the driveshaft to replace the center bearing.
I did the following:
Monkey wrench & channel locks to loosen the locking nut.
Disconnected emergency brake mechanism.
Dropped exhaust from rubber mounts on rear of car.
Jacked up transmission & removed support brace/plate.
Removed bolts for front and rear of shaft.
Struggled to free drive shaft from flex disk until I looked at the one in the box.
Tapped flex disk guide washers free from drive shaft & it was free. No pry bar needed!
Removed old center bearing bolts.
Removed shaft from car.
Separated shaft & tapped out old bearing.
Pressed new bearing in to new holder & tapped it onto the shaft.
Put shaft back together and did the above in reverse order.
Mechanic estimated 3 hours to do the repair. I was done in 4.

Now having replaced the engine & transmission mounts & shocks and center bearing, lower ball joints and upper control arms the vibration noted above and alot more of the rough engine feel and old car ride is gone. Smooth over 80. It just keeps getting better.