You'd have to compare on a year-to-year basis, and you'd have to remove defense from the equation since it heavily weighs WAR in Hamilton's favor.
In his ages 26-31 seasons, Manny put up a 32.3 oWar number in comparison to Hamilton's 23.7. Using this criteria (which is the one that should be used) Manny also has Hamilton significantly beat in WAR.
Some of Manny's advantage because of the era is negated by the fact that Hamilton plays in the Texas bandbox.
Manny's OPS+ for his career, the period you suggested and the period i suggested is not lower than 150 in any instance, while Hamilton's career OPS+ is 135.
Hamilton is not in the same universe offensively as Manny, and making the comparison seems ludicrous to me.