I assume you disconnected the wires from the e unit? If so you need to get the field coil in series with the armature. I think one side of the field is grounded to the motor frame, so, there is only one field wire. Connect the one field wire to one of the brush holders. Connect power to the motor frame and the other brush holder. To reverse the motor, exchange the field connection to one brush holder with the power connection to the other brush holder. To reverse most post war motors, you need to reverse the armature connections with respect to the field windings. Keep the voltage low as the motor will really spin fast with no load on it.