Since a number of posts have come up since I started the spreadsheet I'll let it speak for the details itself.
Summary:
Your torque required seems high... should be force * arm length unless there are other factors... arm angle also plays into this... looks like there is some 'extra' math creeping in here, possibly applying gear ratio's multiple times
Look at Paul's white paper on motor calcs...
http://www.chiefdelphi.com/media/papers/1378
I'm out of time for now, but I check back in the AM.
(AM=morning, not AndyMark, in case clarification is required)
Mark