Answer Kevin, To change the unit from LP to natural you will need 2 of part number WB28K10022 Medium orifice for the Left front and left rear burners, 1 part number WB28K10029 small orifice for the right rear and 1 of part number WB28K10030 Large orifice for the Right front burner. For the oven burners you will turn the orifices approximately 2 1/2 turns counter clockwise. Close off the air shutters and flip the regulator cap to NAt. Read More... Answered by AppliancePartsPros.com | Monday, July 1, 2013