It won’t work so well. What you will need to do is pipe the outlet (the large round fan shaped holes) to the bottom. It might be best take the main board out of the plastic box and mount all of it in your other box. For salt air, conformal coating (think a clear plastic coating) is needed but you have to cover the temp/pressure/humidity sensor and not get any in the sensor holes. Note that Plantower (maker of the air sensors) and Bosh (maker of the temp/pres/hum sensor) have details about how to mount their stuff. The main wifi board should be fine to coat with conformal coating as long as all its connectors are plugged in first.