Absolutely a time where prior planning makes ALL the difference.
Yup, I've yet to meet a plumber who didn't insist that his vent had to go absolutely straight up the middle, centered on the sink.
Best option? Convince the customer to use a long 'light bar,' one long enough to cover your off-center box.
Pancake box attached to a metal hanger between the studs might work as well.
Stupid question time: Do we really need a box? Can't the light fixture be considered the 'box?' Let's see some code on this issue.
