Duralast 7816M Schematic

[warywolfen]

I am setting up a photovoltaic power system, and due to various considerations, am using Duralast 7816M 1KW power inverters.  They're sold by Autozone in the U.S.  I want to connect the outputs of several inverters in parallel.  They must all be in phase, of course.  I'll do that by having them all run off a single master oscillator.  But to make the mods, I need a schematic diagram.  I've spent a lot of time searching the Internet to find one, but no luck.  Does anyone know where to find a schematic?