A fuel supply system includes a fuel pump having an inlet configured to pick up fuel and an outlet configured to discharge fuel. A pressure vessel is in fluid communication with the outlet of the fuel pump such that fuel is directed from the fuel pump into the pressure vessel, the pressure vessel having an outlet port. A pressure regulation valve subassembly is detachably coupled with the outlet port via a male-female interface that positively locks against axial separation upon axial coupling in a first orientation and relative rotation of less than 360 degrees to a second orientation. A reservoir defines an internal space at least partially receiving the fuel pump, the pressure vessel, and the pressure regulation valve subassembly. The reservoir includes an interior wall that obstructs rotation of the pressure regulation valve subassembly from the second orientation to the first orientation.