How to Properly Lubricate Speedometer?

I must of got lucky then cause my '71 had a 'bouncy' speedo. I pulled the cluster out, disconnect the cable/housing, then used graphite and WD-40 to move it down into the sheath. Did that several times, reconnected and no more problems until the car was rear ended on the street. This was wayyyy back in '89 though. LOL