Well, that says they're about 240 mm total height (for some reason I'd been thinking 220), and mine is ~195 mm at the longest, so that's a difference of 35 mm. It also says there is ~160 mm above the insertion line, so I could estimate that I could have ~125 mm above the minimum of where I should insert it, but I'm thinking rootboy's suggestion of holding the stem up to the fork and drawing a line where the expander would be below the threads and calling that my minimum insertion height would be the way to go (assuming it is still tall enough for what I need).