Here is the info I have on which readout boxes can be changed on certain views ...
800/900 Readouts
NAVIGATION:
1-Customize
2-Fixed: Heading
3-Fixed: Bearing
4-Fixed: Split: Cross Track Error(XTE) and Distance To Go (DTG)
5-Fixed: Split: Time To Go (TTG) and Speed
CHART:
1-Customize
2-Fixed: Heading
3-Fixed: Customize
4-Customize
5-Fixed: Speed
BIRDS EYE VIEW:
1-4 Fixed with Depth, Heading, Position, Speed
5-customize
SONAR VIEWS:
1-5 Customize
Rickie