These instructions are using only parts from 10255 Assembly Square, 10278 Police Station and 21320 Dinosaur Fossils set. It is also using spare parts from the original sets. You will get light and dark version of the handcrafted instructions in PDF and bricklink lists in XML. Building alone has only 3324 pieces. Please consider before purchase that you will have quite a lot of pieces left from 10255 and 10278 sets after the build if you choose to build it as alternative build. You can still use it as temporary exhibition of your sets.
This modular building is quite massive and expands across two and a half 32×32 baseplates. It can be divided into three sections – main hall, right wing and left wing. The sections can be connected together with Technic pins like modular buildings. The floor is quite sturdy sandwich construction so you can move the sections without issues even though there is only one big space and no floors.
If you put all three sections together then you can see the fight scene between Triceratops and Tyrannosaurus from above. Parts of the walls of the main hall can be removed in order to get unobstructed view of the scene.
Main hall has mosaic floor which should symbolize asteroid heading to Earth 65 million years ago. It also contains cashier where customers pay entrance fee and boxes where they can store their belongings. For comparison of size of the dinosaurs there is also skeleton of LEGO® Sapiens.
Right wing contains exhibition of Triceratops Horridus and small exhibitions of tools and smaller bones.
Left wing contains exhibition of Tyrannosaurus Rex and again smaller exhibitions of smaller bones end egg nest.
Roofs over the wings are elevated in the middle to accommodate quite large model of the Tyrannosaurus Rex.
Instructions are handcrafted in Studio 2.0 with all details and proper views of the build. You should be able to build this modular building without any issues. Please let me know via private message if something will not be clear. I will try to help you.
Enjoy the build!