All objects use real world scale. Objects are hierarchically parented to the mmelbourne_lamp_mainpart object, so when doing any transformations use that object as a handler. To place the model in your scene simply append the "marksjold melbourne" Collection. Don't remove any objects in that collection, or any nested sub-collections, they are necessary for proper rendering of the entire model. There are special objects named shadeX_fakelight (where X is a following number from 1 to 4) with a special shader that fakes light transmission through the frosted glass cloche. All the models have real-world scale. The shades of the lamps can have two different materials for the frosted glass part - frosted_glass_principled and frosted_glass_v2.0. Both materials are saved inside the .blend file, so you can swith between them freely. It is highly recommended to use high amount of samples. Both frosted glass materials aren't intended to use with eevee render engine. To adjust each cloche rotation do the following:

 - First, set the Transform Pivot Point in 3D Viewport to "Active Element".
 - Adjust the lightX_hinge Z rotation by rotating it along its local Z axis.
 - Then adjust the melbourne_shadeX rotation by rotating it along its local Y axis.  (Lampshade objects origins are located where the connecting bolt is, so you don't have to worry about finding the proper rotation pivot point).