<VV> Calibrate Fuel-Level Sender?

[N. Joseph Potts]

I ordered a new sender for the fuel tank from Clark's that arrived with no
instructions for calibrating it to show empty when the fuel tank is empty,
and full when the fuel tank is full, on the gauge in the dash of my stock
1966 Corsa.
     After I installed it, I noticed that, with the tank fuel, it registered
somewhat less than full. When the gauge shows empty, there is still about 4
gallons of fuel in the tank.
     I e-mailed Clark's about it, and got calibration instructions back that
I'm dubious about (I'll forward them to anyone interested).
     So I thought I'd consult the list to find out what the Voice of
Experience has to say on the subject before I AGAIN go to the trouble of
emptying my fuel tank and removing the sender. I have most Corvair
publications; if the answer is in one of these, just point me to it, and
that'll be all I need.
     Thanks for your replies, which I hope you will POST, rather than
replying to me privately.

Joe Potts
Miami, Florida USA
1966 Corsa coupe 140hp 4-speed with A/C