[ros-users] canonical way to use multiple laser scanners

I have a robot with 2 hokuyo scanners, one on the front, and one on the rear.

What is the cleanest way to merge them into one point cloud, so that the merged
scan can be used for mapping?

I was hoping to use one of the laser_assemblers, but they seem designed only for
assembling scans from a single nodding scanner.

I'm hoping I'm missing something obvious here, because this doesn't seem like it
would be all that strange a setup.

Thank you.

-Aaron