I have just bought some grahamfarish 5plank wagons, and one of them has a damaged coupler. The spring is all bent and out of place, and i was wondering how the base of these wagons is atached to the tops? - Is it possable to remove the top, so as to get to the spring, without damaging the truck at all? - Or can i some how replace the spring without taking the truck apart? thank, daniel N.B. I would like to sort this out quickly is posssble, becuase if i cant it will have to go back asap.