fuel pump sender and new level float


Full Throttle
Hi I am after a bit of advice I fitted a new fuel pump sender unit passenger side and the float arm bit on the drivers side of my audi s3 8l a while back due to the needle being irratic.
But it's still doing the same thing, was there a sequence I need to follow or do as regards to setting up or calibrating the new senders.
Iv seen brief descriptions of you need to drain the tank and do some sort of sequence to calibrate it but I'm not sure if this is right, any help would be appreciated as I need to take his this weekend and would like to have everything in place to do once rather than keep giving myself a headache having my head in and out of the tank lol.