Converting to LP

Inside the stove it say’s it is both lp and ng ng=4wc lpc=10wc . All I need to do to use lp is tighten down the oriafce and changr a setting in the regulator. Is there a piece I need to buy or what do I do. I took the top screw off the regulator and there is a small plastic peice in there that say’s ng natural gas is there a pin foe LP or do I flip something over any help at all please