Just setting about fitting a chip to my N&W J class. The exploded diagrams suggest that it is DCC ready (though I can cope if it is not), but do not show you how to take the shell off the tender. I am reasonably handy, but it is all too easy to break something - or undo every screw you can see, making life long and boring. Is there some kind person out there who can outline the best procedure?
It would help to know who made it? I am not sure about yours specifically, but normally you have to remove the coupler and some screws on the corners. If there are 4 screws on each corner that may do it. If there are two on one end, then you may be able to lift up one side and slide it off of a keeper on the other. There may be a screw from the top covered by a water hatch or something.