You can see on the 1st main board the two lugs or tongues that face upwards. On the bow board there is one lug in the middle and facing down in the image so you don't see it (though you can just make out the two screw heads where it is held on).
Stupidly I can't 100% remember if the bow board lug should face up or down but it's obvious when you go to fit. I think it probably faces up as otherwise it would interfere with the inflatable keel.
Hope you manage to get out on Friday... you might need the all weather gear from the forecast.