demur the files you are dealing with are for ps3/2 board Not ps 3 your confusing yourself!
50-1911 and 50-1912 kits understand!
the engine kits are ps 3/2 board sets one for diesels and one for steam. and you just look up engine item number on mth web sight and download the sound file for your item engine number and chain files which setup your board for the engine you installed in it!
Alan