Mast Steps. Follow up. Install question.

[boatsail]

I posted some time ago about installing mast steps on my boat. Got a lot of great information, so thanks for your contributions. I have come to a decision, but need a bit of advice.

I ordered 1 of the west marine stainless steps.
WEST MARINE Step at West Marine

I will be using it to make a jig so that I can fabricate mine out of aluminum. Here is my question.

Has anyone installed mast steps while the mast is up? If so, any pointers that you could give based on experience? I have ideas, but as always could learn from others if you have done it before or have advice. Thanks in advance.