Hey boombabyy, one method that you could use is to take taxi fair into the base, you'll still need some form of identification and possibly even military identification, but you'd be able to find out exactly what you needed if you attempted entry and talked to the Military Police when they questioned you. You can't get arrested or anything so you have nothing to worry about, they'll happily explain to you exactly what you need to do. Almost all bases have buses that go in and out of base, that would be the easiest/cheapest method. I find it interesting that your guardian can't get on base, since at least here at Camp Pendleton they'll let any civilian on as long as they have a valid drivers license and valid registration and insurance for their vehicle.
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Who dares wins. - Special Air Service