The most recent Lefever double I bought was shipped to a local FFL for transfer. It was shipped broken down and very securely packed, and in no way resembled a gun. In fact, the crowning touch was that the seller had the box taped with Rock Auto packing tape. I wish I could get some of that packing tape because the package literally screamed that it contained automobile parts.
All was not perfect however. It was shipped by UPS, and the package was mistakenly delivered to a Walgreens Drug Store in a neighboring town according to the tracking info. The address on the package didn't even remotely look like the address where it was actually delivered, so the driver must have been smoking crack or something... he was probably a Liberal Democrat. My FFL retrieved the package and told me some other stories about shipping incompetence by UPS and Fed Ex. But the point here is that a package that doesn't resemble a gun is far less likely to attract the attention of thieves or nosy postal or shipping employees.