Battery Equalizer

Does anyone know where the equalizer is located on my 93 Marathon for the house batteries? I see one in the rear for my engine, but don't see one for my house batteries. I'm trying to disconnect each of my house batteries to check them, but need to disconnect the equalizer first.

I called Marathon and found out that I have 4 of the equalizers. I just traced the ground wire from both equalizers to the battery terminal and removed that one first.