Tim, I have never owned a Warship, but have taken the bogie frames off many similar design Bachmann diesel chassis. There are rectangular holes front and rear in the plastic frames moulding, which clip over projecting lugs on the ends of the gear towers. With the model inverted, (can often be held fairly securely be using the expanded polystyrene packaging tray) work in a small flat lever at whichever end of the bogie is most accessible, and simply pry the frame off the gear tower lug. Be warned that the wheelsets will be free to fall out, as the bogie frame also acts as a keeper plate.