EDIT: I later discovered that plugging the 8pin decoder plug the other way around would have solved both the direction and lighting problems, and saved me a lot of programming. Flipping the plug around reverses the polarity to both the track and the motor, and swaps the front and rear lights. Oh well at least now I know that for next time.

Digitrax CV calculator: https://www.digitrax.com/support/cv/c...

Exploded diagram:
https://www.bachmanntrains.com/homeu...

Replacement motor blocks with 5pole motors (while supplies last):

Low boiler version: https://estore.bachmanntrains.com/ind...

High boiler version: https://estore.bachmanntrains.com/ind...