Thanks for the tips guys. Hitting upwards with a hammer, with wood between stem and hammer, didn't help, unfortunately. On the one hand it doesn't make sense that the stem is down too far because based on the length of the bolt, it looks to be about 1/2 way down the steer tube. On the other hand, I do remember that the stem was not willing to go down much further than where I tightened it, so perhaps the steer tube starts to taper early? The fork is a Time Stiletto, carbon, so I have not been really brutal when it comes to trying to twist it out (though I have certainly tried to twist it out), and I have no idea if it's a tapered steer tube or not. I have been giving it persuasive taps, both with a mallet and hammer with wood, but not really really hard taps, don't want to mess anything up internally. Is there any sort of jig for me to get better leverage when trying to push the stem out from below?

-Colin