Style 2
This is the most easy to identify, because of their characteristic fretboard end. On style 2, fretboard takes a "pointed" shape and some of them get into the soundboard. Although, they still have almost no ornamentation.
Style 2 instruments have black celluloid tops and back body binding, rope binding (termed "clown binding" by David Lindley) around the soundhole, white wood fingerboard binding and fancier fret markers than style 1.
Pictures show an original style 2 sold at elderly instruments (elderly.com) for 3000$.