71 idler arm replacment

Replaced the passenger side idler arm with the one from WCCC as my original had some play. Does anyone have the torque-spec for the castle nut? Also, am I to grease inside the sleeve before assembly? Only videos availalbe were for 70 Mustangs and they did not apply grease. The old one came out with the sleave still in place, Free-All took care of that.

For reference this is the aprt and the castle nut I’m referrign to: