To clarify what I was thinking, look at this image of a Zumo 350 that
I have added an orange box and numbers to:
As far as I can tell, the orange box constitutes the "dashboard." from L to R the dashboard has 1. last screen button; 2 Arrival time; 3. Speed; 4. Speed Limit; 5. Map Layers button
I would leave numbers 1 & 5 alone, but would want to eliminate #4,
perhaps eliminate or make smaller or more transparent numbers 2 & 3. Garmin allows some menu choices of changing some of the items that are displayed, but nothing to make them smaller or more transparent (so you can still read the part fo the map they are covering) and no option to eliminate having a field display entirely.