24thatch The original version is an almost exact fit on the Liliput 0-6-0 G Thommen (Waldenburgbahn) chassis. A small amount of material needs to be removed from the bottom of the cab front and the bottom of the inside of the side tanks next to the cab front, approx. 3 mm . This will not be visible from the outside and depending on the modification may not be needed on the 2nd version.