Lion Conversion Kit For 32-Inch 4-Burner Gas Grills - Propane to Natural Gas - 31263. 31263. Conversion Kits. This Lion conversion kit contains all the components necessary to convert your grill from propane to natural gas. The kit includes four natural gas valves, rotisserie burner orifice and a natural gas regulator with a 1/2-inch to 3/8-inch coupler fitting. FOR USE WITH LION GRILLS ONLY. Gas grill fuel conversion should only be completed by a qualified, licensed professional.