Internal Wiring Tips
Looking down on assembly as if it was mounted in a loco & tender,
1.  wire from right side of field goes to right contact of lower e-unit fingers
2.  wire from right brush goes to left contact of lower e-unit fingers
3.  wire from left side of field goes to left contact of upper e-unit fingers
4.  wire from left brush goes to right contact of coil lead plate and also to yellow wire that is connected to transformer.  One magnet lead connects to left brush also.
5.  wire from right contact of upper e-unit fingers goes to left  contact of coil lead plate and also to black wire that goes to control button.
The other magnet lead connects to the same black wire (or coil plate contact)

Internal Wiring Tips
Field assembly is dual wound, each connection contains 2 wires.

1.  a red wire is connected to one of the two wires on one side of the motor field, to one of the brush clips and to one of the wires from the electromagnet
2.  a green wire is connected to the other wire on the same side of the field as the red wire
3.  a black wire is connected to the other brush clip, a wire from the electromagnet and the other field wires