[TowerTalk] NEC and tower power question

[Missouri Guy]

Hi Gents,

I will want to install a 20amp 117V AC outlet at my new tower base.
I'll use a GFCI receptacle and "wet locations" box and cover, 
but I was wondering what the National Electical Code says 
about the minimum HEIGHT above ground for the box?

Also, I should bond the AC protective grounding lead to the tower 
ground, right?

73 and thanks,
Charlie, N0TT