Thoroughly clean the motor bearings, the felt absorbers and the shaft of the armature. I use IPA for this, and let the IPA dry out, lubricate the bearings with light oil, like sewing machine oil, dont use 3 in 1 and never use WD40. You should ensure that the felt pads are full with oil.
When this is done refit the armature to the motor, and refit the bottom bearing, what I do is to gently tap this bearing into place then tighten each screw a little at a time until they are tight.
Check to see that the shaft rotates freely.
Fit the fan and push it down a little way, dont push it to the bottom as it will foul the top of the motor.
Put the motor pulley on and gently tap it down on to the shaft. This action will push the fan down into its correct position.
Clean old grease off the linkages and refit the speed changer arm and check to see that everything works as it should.
Clean all grease off the overarm shaft, relubricate with some light grease, refit the overarm and secure it with a circlip.
At this stage you have serviced the main deck and motor unit.