Posted for "RICHARD Eddinger" <mrsrb1@msn.com>:

There is a system available to tell you when your tank is out and the pump
is still running. It is a pressure valve that goes in the line and when the
pressure goes down you get a light indication on the panel and or the pump
will shut down automatically. My friend just installed it in his Glastar for
the transfer from his aux tanks.
   Dick  mrsrb1@msn.com

[ I'm not sure you want it to shut down automatically, how do you
know how much fuel was transferred? I prefer starting a timer
and pump, a light comes on when the pump current drops and you
manualy shut off the pump verifying the transfer time. -RobL ]