I keep my DL, CHL and POI all in my wallet and they are out and at the window with both hands in view (one holding the wallet, the other handing the needed items) ready to hand the policeman before he even gets out of his car.
I don't say "I've got a concealed weapon," or "gun on me" I hand him all three of the above with the CHL on top.
Doug, this is exactly what I did. By handing the cop your carry permit you're letting him know that you're a law abiding citizen [you bother to get a permit before you get a gun, you let the cop know you have it, etc] and that you're armed long before he has an opportunity to see a gun and come to his own conclusions.
Besides, don't they know you have a permit just by running your tags? Well that doesn't apply to rental cars, but it would in most cases.