How do we replace a player permanently?

It's a very good idea to make a backup before you proceed. Please see
Backup and Restore.
While in a View (default works well)...

  1. Select the player to be replaced in the main list.
  2. Select "Permanently replace Golfer with another player" from the Edit menu.
  3. A step by step wizard will appear describing exactly how to replace the golfer with a new player or current substitute.  You even have the option to move the replaced player to the substitute list.