As requested, here are some pics of the underside of the mower. The first one is of the side discharge chute closed. The second one is with the baffles open and the third with the baffles closed. The fourth one is the MOD sticker on the deck. Basically, close the chutes and you mulch, open the chutes and clippings are discharged.
TC,
if you notice in one of the earlier pics, there is a handle which opens and closes the chutes.