I have attached an STL file (size in Meters) of the PCB which is supported by the bottom plate of the electronic housing. The mounting holes do have a hole diameter of 3.2 mm and it is fabricated with a tolerance of 0.01mm. The PCB needs to have roughly a clearing distance to the bottom of 8 mm. Is placing punched M3 nuts a relative time consuming process? And how would the bottom of the case look like? Is it possible to share a photo of an actual example?