To the roof of FNC, it's 446 feet. But sources that I find say to the top of the spire is 493 feet. I don't know if it's just me, but FNC's spire looks much taller than 47 feet, even taller than Chase Tower.

Maybe it's referring to the lower, thicker half of the spire? If so, then how tall is the whole spire (including the upper, thinner half)?

Thanks! (:

493' should be the official height since FNC's spire was part of the original architectural plans - not just an antenna. But I see your point, FNC has extra antenna above the spire/beacon section that pushes it higher. How much I don't know.

Oh I see, I didn't realize that the antenna was a later addition.

I'll try to help. If my calculations are correct, then:
http://radikal.ua/data/upload/49112/05615/72fe67ecdb.jpg (http://radikal.ua)
Accuracy is 99 percent.

By the way, comparison:
http://radikal.ua/data/upload/4efc3/6895e/248fa8e153.jpg (http://radikal.ua)