Navel piercing and military enlistment?

I have a navel piercing and I am getting a tattoo on my lower back (a tribal eagle). I want to join the National Guard. Will this disqualify me? I know I can't wear the navel jewelry in uniform but if I only serve "one weekend a month and two weeks a year" can I wear it the rest of the time "as a civilian"?
How can I keep it from closing during basic training?