Hull is the same. The width of the gunnels is a subtle difference but is worth mentioning. on a SSN the gunnels are about 6 to 8 inches wide. On the narrower SAN, pry 3 or 4 inches wide. So the SSN will have less interior space than a SAN. It's nice when you're climbing around the tower, but does sacrifice a little space.
The narrower gunnels started in 2002. Prior to that they were wider. In 2002 the interior is also a little deeper. It may not be much on paper, but you can feel the difference. It was one of the main reasons I was looking for a 2002+ SAN.