Hi All --
I installed one of the Loksound v5 Kato for USA sound decoders into an N-scale Kato RS-2, but this required modification to the frame to fit the decoder and the speaker.
I liked it so much that I bought two more and installed one into one of my N-scale Kato SD40-2s. This is basically drop-in. I did purchase some 16x9mm speakers from Digikey and printed a custom 3D speakerbox that fits nicely under the decoder board at the back of the loco and with a notch on the frame. I installed the S0710 sound file.
Here is a short video of the result:
