Hi Nick
Question to not just you but anybody looking to replace the pivot bearing, are you replacing the bearings because they are bad or because they grease in them has dried out or become lumpy? True wear can be felt as loosness, but on all three of my trucks what I found was these pivot bearings didn't turn smoothly and seemed lumpy.
The manual says they can not be repacked, guess what the manual is wrong. But being 38 or so years ago restoring a CMP in the US spare parts and resources like MLU didn't exist. Figured what the hell put the ball units into a bucket of solvent and disowned the grease out of the "sealed" pivot bearings.
You clean the bearings and make a tool to force new grease into the bearings. This simple little tool is made of a length of threaded stock that has been center drilled and tapped to take a grease fitting and side drilled to allow the grease to come out between the nuts. Then with washers of different sizes different small bearing can be re-lubricated.
It may take several repeats of the cleaning and regreasing and turning the bearing to get all the old grass out. Now to the guestion does this aproach work, yes I've gotten many years out this approach.
Cheers Phil