You didn't post the engine size, but typically it is best to relieve Fuel Pressure at the Fuel Rail / Injector Rail.Looks like a Schrader Valve
Disconnect the negative battery cable to assure the prevention of fuel spillage if the ignition switch is accidentally turned ON while a fitting is still detached. Loosen the fuel filler cap to release the fuel tank pressure. Be sure the release valve on the fuel gauge is closed, then connect the fuel gauge to the pressure fitting located on the inlet fuel pipe fitting.
CAUTIONWhen connecting the gauge to the fitting, be sure to wrap a rag around the fitting to avoid spillage. After repairs, place the rag in an approved container.
Install the bleed hose portion of the fuel gauge assembly into an approved container, then open the gauge release valve and bleed the fuel pressure from the system. When the gauge is removed, be sure to open the bleed valve and drain all fuel from the gauge assembly. When fuel service is finished, tighten the fuel filler cap and connect the negative battery cable.
Yes, you can relieve pressure at the valve.Disconnect Battery, wrap with rag & you should wear safety glasses, then push down on middle of valve, to release fuel