same thing, except place the waypoints FIRST, then send the message
or have race files, that record waypoints. when the person hits a hotkey, it opens a certain race file, the waypoints are placed on the map, and the message is sent.
Also, add a private race feature... so if there are 30 players on the server, and you only want to race with 2 of your friends, you can select them from a menu.
'course, it depends on if all of this is possible or not.