And so what does the third picture represent?
Off the top of my head, there's a few different six pin decoder versions running around from ESU:
basic six pin
six pin with attached wires for capacitors or similar (spitballing, please check the manual)
six pin but at 90 degrees
six pin but separate from the board and connected with ~3 inches of wire
For an FVM locomotive, the first two are fine, the third (90 degree mount) doesn't work, and the last depends on the unit... very awkward to impractical in a GP60, less so in a 70ACe due to the extra space required by the wiring harness.