1967 Satellite fuel gauge question

Hi guys a while ago i removed my dash do to some issues with gauges and lights, after cleaning all contacts all went back to normal except for my fuel gauge, it worked but not properly, i replaced the sending unit and it helped some. My issue is when i fill the tank , the gauge shows full like it should, the problem is when the fuel gauge is at the empty line i still have over half a tank. Correct me if my logic is wrong, i am thinking i will remove sending unit, bent the float up a bit this should help, does anyone have an idea how much to bend it? thanks pete
Author: sendust