As with many of my projects, things that seem simple, are not so simple. I came across a few issues while switching from a PC680, to the EarthX 680. I have a few pictures, and some configuration instructions that may help someone who is doing a similar upgrade.
If your battery box is located aft and you have the aluminum battery hold down, you will likely need the terminal adapters that EarthX sells. This is because of the difference in terminal location on the two battery's.
Next, Its probably a good idea to insulate the hold down bar from the terminals in case of accidental contact. For insulation, I used baffle material encased in a big piece of heat shrink tubing. The heat shrink tubing does a good job of holding the baffle material in place on the hold down bar. I also made a small pad out of the baffle material. This sits on top of the battery to provide some room between the terminals and the hold down bar.
The EarthX fault monitoring instructions were a little lacking. I found SkyView configuration instructions on the Dynon Forum. They worked great! The last step is important. You have to actually display the widget. See below.
1) Connect the EarthX fault monitoring wire to any unused General Purpose input (type = A or C) on the SV-EMS-220. (Pins 4, 7, 8, 9, 10, 11, 12, 20, 21, 22, 23, or 31)
2) Configure the input in the EMS SETUP> SENSOR INPUT MAPPING. FUNCTION = CONTACT, SENSOR = CONTACT, NAME = EARTHX (select CUSTOM and enter a suitable name)
3) Configure the EARTHX CONTACT in EMS SETUP> SESNOR SETUP.
ALARM = SELF-CLEARING
MAXIMUM GRAPHICAL DISPLAY = 5.0 VOLTS
MINIMUM GRAPHICAL DISPLAY = 0.0 VOLTS
RANGE 1
ENABLE = YES
NAME = ALRM
COLOR = RED
TOP = 1.0 VOLTS
BOTTOM = 0.0 VOLTS
RANGE 2
ENABLE = YES
NAME = (NOT SET)
COLOR = BLACK
TOP = 5.0 VOLTS
BOTTOM = 1.0 VOLTS
Ranges 3, 4, and 5: ENABLE = NO
4) Place the EARTHX CONTACT widget on the 100%, 50%, and 20% EMS screens using the EMS-SETUP> SCREEN LAYOUT EDITOR
Hopefully this helps someone else!