Sending unit?

[BigAl331]

Replacing my sending unit and need advice on which way to point the float.

The one that was in the boat, I'm assuming was bad, when the tank was empty the guage indicated 1/2. I shorted the lead to ground and the guage went to empty, so I guess the guage is good. To late now I've pulled the sending unit out.

The last time I took it out when I was running aobut 20 it indicated full which I took as half. When I slowed down it went to 3/4 (1/4 tank). So which way would be best to point the sending unit?