I guess I get to designate myself as the hero. I'll answer my own question in case anyone else is interested. I took mine to the dealer and they let me watch the repair. Here's what they did: removed both of the front turn signals which exposed pinch bolts holding the headlight assembly in. Then they lifted the car, loosed the bumper and pulled it forward about 2 inches. Two bolts on each headlight and the whole assembly popped right out. Wiring harnesses are self explanatory and obvious to replace.
This is a highly common problem on the Volvo's particularly on the low beams which get more use than their high-beam partners. The connectors get hot and brittle and you'll see one node of the connector that is shinier than the other, indicating a poor connection.
Anyone has any questions about this one, I'll try to help. Dealer was enormously helpful. I have ultimate trust in this Volvo dealer after dealing with them on this.