Bachmann's instruction manual for the C-19 is not very clear as to thich screws to remove to allow installation of Kadee couiplers.
On the engine under the pilot there is a rectangular cover plate held with two fairly large screws. Remove them, take out the Bachmann coupler. Unscrew the small screw in the middle of the shank, reemove the Bachmann coupler and install a Kadee #916 coupler on the Bachmann shank.
On the tender, in the middle of the end sill, from the bottom, remove the large screw at the center of the plate, then the two small screws. Change the coupler as above and put it all back together. I found it handy to take out the tender truck screw and move the trusk forward to gain a bit more room.
I have sent this to Sam Clarke at Kadee.
Glenn Joesten