New Auto Meter Gauge/Sending issues

OK guys here are the results from tonight's meter party. I took the sender out and at empty it reads dead on 73 ohms. When I move the float all the way up I read 8 ohms. I slowly swept it from top to bottom and the meter was sweeping higher and lower with the movement so the sender is working properly. Our only thought was that there was not enough fuel in her. So I went and bought five more gallons and now it reads 1/4 tank. I put another five in it and it is almost reading full now. It is reading in between half and full and there is roughly 14 gallons in the tank so it seems as though everything is working as advertised. It just drops a little faster once on the empty side. Additionally this was the first time that I put fuel in the new tank so I noticed when the sender was removed that the pickup tube/float do not sit all the way on the bottom of the tank. I would say that there is at least 2 gallons of gas in the tank before it even hits the float. The fuel pickup tube is lower than the float which would make sense on the readings. Basically when the first 5 gallons went in, the sender only detected three or less gallons due to the free space. I dont think she is quite full yet so I will keep adding fuel until it gets to the top and I think it should be good. Thanks for all the help guys.