Fuel gauge help

[Evileye5060]

Hi I change my fuel pump and sender as it was not showing the correct amount of fuel I would fill it up and would only take around 60 odd litres when saying empty then would only show 3/4 full When filled up . so had it changed the other day I filled it up and it only took 64 litres and had 8 litres put in it when the pump was done ,the gauge showed just below full then slowly crept up to full then when you turn the van off and back on it will show just below full Again then creep up as you drive any ideas would be appreciated iv checked all the joins to the bcm And put electrical grease on them still no change also done self test on the gauge and seems fine .the vans a 63 plate custom 2.2 125 limited
.thanks