On LED's and Gecko Tunings

Two quick, and perhaps silly questions:

Will a 6K resistor be enough with my 50-60V power supply, to light an
LED and not fry it?
I'd like to have a neat light telling me if my power-supply is on, and
the old external HD case I'm using already has one built in... So..

R=V/I
R=(60/0.01)=6K?

Goodmath? Wrongmath?

.. And.. Which is better, tuning gecko-drives with the motor attached,
or not attached to the leadscrew (ie. Bench or field?) I mean, attached
it might break something if it starts violently oscillating, but then,
wouldn't it be better if you adjusted it when it was actually moving the
table? Or is a combo of both best? Your experience, please!

OkayThanks!
~Abby