^Well, after completing the model, here's my breakdown of numbers, which have been refined from earlier, rougher estimates I posted a few pages back:
Office+retail levels are 66' combined.
2 mechanical floors @ 21' each.
4 trading floors @ 18 each
Last trading floor+ podium roof comes out to 21' high.
That leaves a podium 201' tall.
On top of that, there's 3 mechanical floors of 27' a pop.
Then 53 typical office floors of 13'6" each, which makes for an occupied height of 997'6".
Two more mechanical floors of ~22' brings you to the roof at 1041'6"
A series of 3' and 13'6" high glass and steel panels brings you to a fin height of 1073'
Subtracting 1073 from 1170 gives you 97' long spires.
66+(2*21)+(4*18)+21+(3*27)+(53*13.5)+(22*2)+31.5+97=1170
This render, BTW shows the spires at 85 feet tall, before I finished proportioning out the lower floors. It made the building look a bit...chunky and inelegant.
This, and all later renders, show the lower roof and longer 97' spires.