Starting with the base on a flat even surface,glue and nail 04-102, 04-103 and 04-106 to the base using the same method as the ground floor ply component to the base frame assembly.
Once glued and nailed, leave for 24 hours for glue to set.
This stabilses the model before you proceed to add the first floor and roofing components.
After 24 hours glue drying time, position the first floor by using the 12 inch dimension of component 04-107 to gain the right height between components 04-102 and 04-103. Glue and nail as before.