I have a Pennsylvania Loco #4656. The unit was built by Williams Reproductions Limited from Columbia Maryland. It is a Diesel SD-45, Pennsylvania RR. . I want to set the e-unit to always go forward. The old Lionel's have a manual switch but this is a newer electronic e-unit. Can I easily set it for the forward only direction? If I set it to always go forward can it be set back is desired? Once I opened the unit I found that the card is different than I see in the documentation and card image on this forum. It is probably older than I thought or the current cards. The box is labled Williams Electric Trains and stamped PENN RED SD-45 4201 REV
Thanks