Top left post is the center roller pickup, lower right is the field connection, top right and lower left are the brushes.
To wire it in one direction only, jumper the top left to the bottom left post, and the top right to the bottom right. If the motor runs in the wrong direction, jumper the top left to the top right, and the bottom left to the bottom right.
If using the e-unit, the top left post is wired to the hot side of the e-unit coil, the outer 4-finger lead to the field terminal (bottom right) and the center 4–finger and bottom 2-finger to the brushes (doesn’t matter which one).