Take it to a police department...?
I'm actually suprised that Nate DOESN'T have an answer.
I doubt most dealers would let you do that BEFORE you bought it. In fact, its probably illegal.
Could an officer be dispatched to undertake such a task? Have any LEOs here ever done that?
That's the only bad part about purchasing firearms from someone who doesn't have an FFL.. you run the risk of buying a stolen firearm.