Step 1: Clean the Propshaft and the Saddle
Use some oil and clean out the holes where the joint will go. Also clean out the ridges where the circlips are to go. Check there are no large bits of grit that will make it not run smoothly. Do this for both the propshaft and the saddle.
Step 2: The Saddle
Carefully take both the caps off of opposite ends and carefully put the joint in so they are inside the slots. Then line up one cap with the joint and hit the saddle down with a hammer, on to the cap, do it far enough so that they won't seperate(Photo 1). BE CAREFUL because if the cap is not put on square then some roller bearings might come loose and you're back to square one.
Then using the same technique put the opposite side cap on, ensuring that it is lined up properly.
Use a socket and a hammer to tap the cap down until you can feel the ridges for the circlip(Photo 2).
When you can feel the ridges on both sides you are ready to put the circlips in. Using circlip pliers put in the clips and use a little screw driver to ensure they are in by pressing it down. Do this for both sides. (Photo 3)
Step 3: Grease Nipple
Screw in the grease nipple. It is much easier to do it now as you can't easily get to it when the propshaft is also connected. Tighten it with a socket.
Step 4: Propshaft
Do the same for the propshaft as you did for the saddle. Remove the caps, align one with the joint and hit the propshaft down onto the cap(Photo 1). Repeat on the other side. Hit the caps down futher using a socket and a hammer,(Photo 2) do this until you can feel the ridges. Then insert the circlips ensuring they are fully in using a small screwdriver.(Photo 3)
Step 5: Finish
Using a grease gun put some grease in. Then move the joint around, putting more grease in. This just makes sure that the insides are fully greased. Just double check that all circlips are in and you are finished.