Gluing up the wedges on to the sliding hatch rails and starting to fit the rails on the cabin roof

Gluing up the wedges needed to let the sliding hatch slide along the lower hatch rails level

Once the glue is cured then the excess glue is cleaned off and the slots cut into the inside faces of the rails 

Starting to fit the rails in the correct position to ensure the hatch slides along the rails once they are fixed down into position 

the inside faces which have thew slots cut into them have to be adjusted to make the hatch slide along the slots once the rails are fixed down