I've run into this with the replacement pickup/sender from Wilkinson.
The new one isn't calibrated to the tank and sender. It has the solid nitrofil float on it.
It took me a while to figure that out and the best way to do it is use the Bosswrench method of removing the rear driver side window.
So the instructions from me are not to bend it, "calibrate" the arm.
There are no instructions from Wilkinson. His response was "what?" "huh?"