gtbro1, I always use the same "alias" name when I have gear sent to my PO box, so the ladies that work there, know who I am, I'm in there all the time, so I have a half ass decent relationship with them. I have never had to show ID to pick stuff up, I just tell them I have been expecting a package that I know is too big from my box and ask if it has showed up yet, and tell them the box number and name. They check, and if it's there, they hand it over. Never had to show ID once, and I've had lots of boxes that were too big for my box sent to me. I've never had a problem with not having to show ID to pick something up.
But it also helps asking for it in advance, (when I KNOW theres no way its had time to get there yet), so they know I'm looking for it and expecting it.