Well, the bees won! I couldn't get to them though the roof or soffet due to multiple roofs and soffets(original house built in 1850, modernized at least twice since then)so I went inside and cut a 10 by 12 inch hole in the ceiling. Yet another roof layer about 5 inches above the lath/plaster, but no bees. Next I drilled several 1/2 inch holes in the wall to check there. Blown in insulation and behind that another wall! The total wall thickness is about 14 inches and I know there are at least three separate walls; plaster/lath, brick, and wood! I closed everything back up and told the homeowner that the bees are just inaccessable without doing several thousand dollars worth of destruction. The next option is a trapout, which I will start in late April. And to add injury to insult, I got popped on the eyelid while closing up the roof! :( Their entrance is behind the gutter, so that is going to be a challenge as well!