How to add oil to Realistic LAB-400 tonearm cue ?

The cueing lever lifts the tonearm but when I go to lower it on the song I want it drops really fast. Does anyone know how to add oil to the LAB 400 tonearm cueing mechanism? I already looked at the service manual and it just shows an exploded view of the parts but does not show or tell you how to replace the oil. I already have the silicone oil I just don't know how to get it in there. <!-- / message -->

Thanks. :confused5:
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