If all you have is 2D (DXF, DWF, PDF, etc.), then you can use them as references to create 3D objects that can then be converted into a Block. The Blocks can then be placed as needed.
First, make sure that the 2D references are accurate (you may have to scale in X or Y, or even redraw according to the dimensions).
Then, you can Simple Extrude the 2D references, even going so far as rotate and position various views (XY, XZ, YZ) so that they can overlap and 3D Intersect to produce the desired object.
TC Pro Platinum 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
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