It's the best info we have to go with. It's safe to say he wasn't 190. It's almost as safe to say he wasn't 170. He was wee.
Re: "How would These matches go with guy's not too far off from Jeffries era? All fights are 15 rounds." Jeffries Vs Dempsey (1919 version): Jack Dempsey. Jeffries v Langford (1905-06): James J. Jeffries. Jeffries v Jack Johnson (1905): Jack Johnson. Jeffries v Tommy Burns (1906): James J. jeffries. Jeffries v Willard (1916): James J. Jeffries.