Here one can find bottom plates for some FPGA development boards, all holes are made for a 2.5mm screw.

Mimas v2
mimas_v2_bottom_plate_01.stl.zip
EP2C5 Mini Board (CycloneII EP2C5T144) FPGA Development Board
ep2c5_mini_board_bottom_plate_01.stl.zip
Mojo Board
mojo_bottom_plate_01.zip

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