You need to remove the bearing cups from the new universal joint journals, coat the needle bearings in the bearing cups with a thin layer of the grease that is present on the journal and apply the grease with your finger. Install one bearing cup part way into one side of the yoke, turn the yoke ear towards the bottom and install the cross into the yoke. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until it is flush with the yoke ear and install the opposite bearing cup partway into the yoke ear. Make sure that the trunnions are started straight and true into both bearing cups, press the opposite bearing cup into the yoke ear, and install the bearing retainer in the retainer groove. If the retainer does not seat, spring the yoke slightly with a firm blow from a dead blow hammer.