The 324 is a 30 hull with a much different interior than the 30C or 30U, a shallower draft keel, & carbon spars. Only nine or ten 324s were built during a very short period in the mid 1990's. They have a higher aspect ratio (taller) carbon fiber rig, mast/wishbone, 22% more sail area (689 sq ft) than the 30s (540 Sq ft) and even more than the 33s (669 sq ft), a shallower draft 'winged' keel, and no teak on deck.
The layout below decks is also very different from the 30C (Classic) and 30U (Ultra)