I have found a little more info on the subject. The barrel is indeed pressed in. In fact, I guess you need to heat up the receiver to get it in.
I was hopping that this would not be an issue, since I have the "upper" unit, but the pins must be peened into place with the barrel removed.
I like the AK design, but have been spoiled by the modular set up on my AR. I think the cost and risk of damage far out weighs the advantage of the short barrel.