I have converted my 02 Sport to an SE. The finishing touch is the gooseneck. I ordered a part from Hobie, which arrived looking nothing like the gooseneck on my 86 H17:
It has larger side plates, with two holes; one for a sheave, perhaps, and the other as the downhaul anchor.
If I were to install this, aligning it to the two holes in the mast-bottom casting, using a bolt in each hole, it would not be able to rotate. So if the sail lifted the boom, the pin that sticks out of the end of the boom would bend (or worse).
Is there a part missing?