Here's the crash course:
http://www.classicseacraft.com/literature.htm
http://www.classicseacraft.com/specifications.htm
Read this stuff while you await replies. Enjoy. Avg. dead-rise is 16 deg on 20, 20 deg on 23. But remember this is a variable dead-rise hull.
Although very capable offshore, the 20 was designed as a bay boat, the 23 pure blue water.
Here's a visual comparison a forum member posted a while back
