A faulty fuel sending unit has been diagnosed as the cause of a fairly steady dripping gas leak from the upper rear section of the tank on my 1991 940 T sedan. Does this make sense?

No other diagnostics would seem to point to this as the problem: fuel gauge works fine, no noticeable rough idle/power/acceleration issues.

Could someone explain the potential connection between a gas leak and the condition of the in-tank sending unit? And before I spend $375 on a new sending unit (+ replace fuel pump while I'm at it...), might the culprit be a faulty component part of this unit -- some gasket or o-ring -- that could be replaced at much less expense?

Thanks,
Peter