A method for integrating a fuel cell unit into a vehicle structural component, includes determining an available receiving space in an interior structural component of the vehicle, providing two casing parts assembleable to a closed casing, providing a fuel cell having an anode, a cathode and an electrolyte, assembling the casing parts and the fuel cell to form the fuel cell unit, and inserting the fuel cell unit into the receiving space. A casing part is additively manufactured such that the fuel cell unit precisely fits into the receiving space. A casing part includes an exterior fuel inlet and an interior fuel distributor for leading a fuel from the inlet to a fuel outlet couplable with the fuel cell. A casing part includes an exterior oxidant inlet and an interior oxidant distributor for leading an oxidant from the inlet to an oxidant outlet couplable with the fuel cell.