I used the S version as it has all the connections needed for a forney loco. I tie the lights and smoke to the 10 volt source and change CV 60 to 160 to reduce the voltage to the lights. Also change CV 114 to 128 for F6 smoke no reduced voltage as the smoke can have 3 heats by changing CV137, 138, 138 plus cv132 to a 72. This gives a wisp at idle (137), smoke at run ((138) and lots of smoke under heavy load, accelerating (139).
There are 3 ways to add bell/whistle sound sensors in LGB engines.
1 For the forney, LGB has a dual sensor that mounts on the rear freight truck. Same unit on Moguls with sound in the tenders.
2 glue reeds in the rear bottom of the motor block
3 get the LGB motor block sensor board with hall effect sensors.
I prefer the 2 glass reeds on the bottom of the motor block, by far the lowest cost method. Note left rail is bell, right rail is horn/whistle.