I finally figured out how to add an ESU 58923 and an OWS 8x15mm speaker to the Arnold/Hornby U28C. I removed the original power pickups, then machined away bits of the top frame, and 3D printed a backcase for the speaker. I removed all of the wires that were not needed from the 58923. Then, I "underslung" the 58923 and the speaker underneath the main Arnold circuit board with Kapton tape. I clipped the vertical power leads at the top of the trucks, and soldered 30ga wires to the power leads on the inside close to the gear tower. I connected the motor leads to the underside of the main PCB, then soldered the power wires from the trucks to the original contact points on the main PCB. I ran longer wires from the speaker contacts to the 58923 PCB (yellow and green). The power feeds and pick up wires tuck neatly under the top circuit board frame. Not shown- I soldered the slider bronze tabs to the truck vertical extensions- carefully... This eliminated a weak spot in the power feeds. Uploaded the U25/28 sound file from ESU.
Then, when I went to make the pictures, I saw that I have "lost" the front handrails- somewhere on my bench, I suspect...
