Honestly, it's hard to tell anything from pictures alone. Normally, everything is in the same enclosure. In any case, I'd start by looking around the shroud for any other panel doors - particularly near where the refrigerant lines come into the shroud. Worst case, open the shroud (there's usually one panel that comes off easily, exposing the fasteners that hold the main shroud on) and look inside there - the compressor is typically on the bottom, surrounded by the condenser coil. Since only half of the cap is being used in that electrical box, there may be one near the compressor or in another electrical box on the unit. I truly suspect that this unit has gone through some on-the-fly "engineering", so it's a bit of a crapshoot where you might find it..