Edge 1050 multiple lights battery monitoring Anyone know how to do this?

Hi all, I have an Edge 1050 and a Varia 715c. I have a data screen for road riding that displays battery life for my shifters, power meter, and the Varia all on one screen, very useful.

I just added a Garmin UT800 headlight to the network, and now I want to add a field to that data screen to monitor its battery life as well. Unfortunately the only option I can find is Lights>Battery Life, which only shows an individual battery even if both lights are on.

This field works with either light but I can't replicate it to show both light batteries at once.

Anyone know how to do this?