I also installed a BW1000 Tsunami Sound Decoder which also runs the lights. An NCE D408SR decoder runs the motors due to its 4A peak. For switching, the tsunami alone may have been enough. The unit does run and sound great. I am using a 1" speaker with a Soundtraxx baffle behind it.
I also added wipers from Rod Miller to also get power from the other wheels as only 4 out of the 8 wheels originally supplied power to the boards.
Here are a few photos. One even shows the decoder installation.