You are right that what you have is probably a bad support bearing. You are not correct as far as the number of U-joints. The front shaft is attached to the transmission by the front U-joint and supported by the carrier bearing in the middle of the car. The rear driveshaft has a splined shaft which inserts into the rear of the front shaft-then a middle U-joint and then a rear U-joint which attaches to the differential. The middle U-joint allows for the up and down motion of the rear suspension. The U-joints and (maybe?) the carrier bearing are year and/or transmission specific.
The carrier bearing is a close fit to the front driveshaft and sometimes will just slide off if you are lucky. A press is rarely needed -- supporting the bearing (by hand) and having an assistant using a mallet to the driveshaft rear end should get it moving. Clean the area where the bearing has to slide and a little lube doesn't hurt.
TAKE NOTE - the driveshaft halves are balanced together and the U-joints have to be aligned in a specific manner. Mark the two halves. A correctly assembled total driveshaft will have the very front yoke and the very rear yoke aligned so that they could form one complete U-joint. In other words -- if the very front yoke is vertical -- the rearmost yoke must be horizontal. If you fail to mark the halves (assuming they were correct to begin with) there could be two solutions--only one of which would be in proper balance. -- Dave