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Some rough considerations for each part include:
Take a read on Elec’s Enclosure design guidelines
Heat dissipation for hardware components on PCB
components should also not be in direct contact with the cover
Mounting position in the car
Is there space for your design?
How does your cover mount to the car?
Where does your board mount?
How can the cover be attached/removed for elec to access the components easily?
Waterproofing
How extensive should the waterproofing be? Where direction does water come from that needs protection? (We are not looking for IP67 here, but some might need more protection than others)
gaskets? cable glands?
Manufacturing
Probably 3D printed
Weight and dimensions
how big/heavy is your design? What infill are you using when 3D printing?
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