Help, the front truck on my rail truck has dropped off. A screw holding it to the frame of the truck has worked lose. I have looked at putting the screw back in but it is covered by another plate which holds in two sprung plungers and that plate is held to the front truck by two screws that one cannot reach once the truck is held in position under the main body. Has anyone had this problem before and can you give me a step by step description on how to reconnect the fron truck to the main body and frame. Thanks