I took the old SC driver board and lifted the legs of the mosfets and sho nuff' I found a shorted one. Whoo hoo! This means it should be possible to fix the old SC board, and fix the newer one that also failed. The part # is 5N2307. Oddly, when I go to eBay and search for it, the descriptions all mention Panasonic, and sometimes the family of TV.