Schematics are online! As a bonus, I designed 2 verisons of the packages for the SIM800 modules, one with all the pins and one with only the mandatory pins to get the module up and running. I had to resort to this trick to save space for the tightly packed tracks, that on the PCB are spaced at 6/6 mil. A better board manufacturer would allow me to decrease the size of the tracks, but that's for a future prototype. I don't like having the modules "flapping around" in the breeze with most of their pins unsoldered, especially in the mechanical stressful environment that is a vehicle.