You should put the pressure connection to the switch at the tank. If the switch is mounted on the pump, you can run a tube from somewhere at the tank to the switch, or you can move the switch itself to where it measures the tank pressure and run wire from the switch to the pump.Originally Posted by SC Handyman
If you have a submersible pump you should have a pressure relief valve on the inlet side of the filter. If you have a shallow well jet pump you don't need a relief valve if the pressure capability of the pump is less than the pressure rating of the filter.
You need to pay a lot of attention to the pressure drop across the filter and you should have a gauge on both inlet and outlet of the filter.