First, you should be able to delete the unused widgets in SETUP MENU > EMS SETUP > SENSOR INPUT MAPPING… menu. Then, in SETUP MENU > EMS SETUP > SCREEN LAYOUT EDITOR.
Second, your user config file should have a section that starts with an entry like this:
ems_user_cal={
valid=1
name=FUEL R LEVEL
First, make a backup copy of the original file and store it in a safe place. Then, rename the FUEL R LEVEL section to FUEL LEVEL. After that, you could also set valid=0 for the following two sections that are for FUEL L LEVEL and HEADER LEVEL, but that may not be necessary if you deleted those widgets from the screen. This of course assumes you used the right tank input to the EMS for your tank. That should work, but I've never done that, so I won't swear by it. If all else fails, you can restore the backup file.