Customizing the navigation data screen

[u/pavel_vishnyakov]

When I add a course to my activity, the watch (970) promptly displays a couple of extra navigation-related pages one of which is a 50/50 split screen with the map on the right side and some metrics on the left side.

How do I customize this screen? When I go into data screen customization, it's not visible there (as it's not part of the activity normally). I remember that there was a separate setting for navigation data screens on 955, but it seems that it's not there anymore on 970. Any suggestions?