A system including a plurality of multi-tube fuel nozzles each having a plurality of tubes extending in an axial direction, wherein each tube of the plurality of tubes includes an air inlet, a fuel inlet, and a fuel-air mixture outlet, a fuel nozzle housing including a first outer wall extending circumferentially about a central axis, wherein the plurality of multi-tube fuel nozzles are disposed in the fuel nozzle housing, an inlet flow conditioner removably coupled to a first end portion of the first outer wall, wherein the inlet flow conditioner includes a plurality of air openings, and an aft plate assembly removably coupled to a second end portion of the first outer wall, wherein the aft plate assembly includes an aft plate having a plurality of tube apertures, and the plurality of tubes extend to the plurality of tube apertures.