The temp and depth reading in the "full screen SI view" cannot be changed to other readings...(I also wish we could have speed here)...
You can turn off the "Full screen SI view" to have access to the "Readout" boxes that will show down the left side of your 898 screen...(I think this setting is under the "Sonar" tab in the main menu called "SI Readouts..On or Off"...)
Then you can change the readout boxes to several different choices by going under the Setup tab in the main menu system to "Select Readouts"...
There are 2 categories of choices in the Readout boxes....
1. Readouts that show on any chart or navigation view..
2. Readouts that show on all other views...
Rickie