I needed a top case that supports the 3.5 TFT screen of my Raspberry pi 3b+ and also can be wall mounted. I use the bottom part of Sneaks' modular case “__raspi_bottom__1_05-RP3BP V75.STL”.
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rpi_3b_screen_top_v2.stl
Added vent holes and added allowance to easily snap with the board.
The author remixed this model.