I have an old model Overland 4-8-4 that needs lubrication. I can't figure out how to remove the shell - I've found and removed one screw that was behind the trailing truck, but I can't find any similar screw anywhere near the leading truck. Apparently with some older models there was a screw underneath one of the domes, but with this model it appears to be one solid piece of plastic. I've gone over this model with a strong light and a magnifying glass, but I'm totally stumped!
If its anything like the Blue/white box Niagra theres two screws under the cab, once those are out it takes some wiggling and it should come apart.