SHOULDER BOLT mounting advice

Hello,
what is the proper way to mount an axis for 2 parts to rotate with a vertical axial force of 100 Kg with part 60mm high?.
Should an extra washer be added on the bottom to limit the friction? What type of washer?
What should be the ratio between diameter and material tickness?
Should the contact be in the 2 positions (green on pictures attached)?

Is you do have a link to documentation to learn about this type of mechanical organ, thanks to share.
Thanks for sharing your knowledge.