SI Readouts OFF in the Sonar main menu.
You can turn off individual readout boxes too for non-full screen SI views.
The 1199 does not have left side readouts. There are two sets of readouts.
Those are at the bottom and you can turn all the readout boxes off for regular views and the Navigation readouts.
Humminbird Helix 12 SI, 1198c SI, 1198c SI, ONIX 10 SI NT, 360, RC-1