Some glue needed
Depending on the printing quality and resolution, you may need to shave/glue the supports to fit. Given that this is the first prototype, that's not such a bad thing. :)
Trial and error...
Got an RPi case from Thingverse ad added the trenches to fit the supports and face.
Designed each device (camera, PIR, LED) separately, printing it until it fit, then bundled all together with random support lines.
This is just a prototype, I want to make the camera support movable (up/down) and close the whole thing, to avoid dust accumulating.