Fuel leaking at sending unit again, and tips or tricks?

Hello everyone
Well, I have one more frustration on my car relating to the fuel sender.
I replaced the tank and sending unit in 2006, but did not solve my original problem of the gauge only going up to the ¾ mark when the tank was full, but it worked and at least let me know there was fuel in the tank.
Last year the gauge quit working and the tank showed empty all the time.
I pulled the sender out a few weeks ago and found the float was full, I replaced the float and put it all together using a new seal at the sender and filled the tank to check the operation of the sending unit.
The car sat for a week and I now have fuel seeping from the front of the fuel tank and dripping on the floor. This may seem like a simple question but is there any trick to getting this thing sealed? I used a new rubber gasket (Mopar part). I took this apart last year as well and put it back together with the old gasket and also had a slight seep. I was told ALWAYS use a new gasket and there should be no issues.
Anyone else struggle with this?

i had a similar problem, but it turned out to be cracked rubber fuel lines and a steel vent line loose in the tank. i noticed the leak after i changed the sending unit. turns out gas was running from the vent line down the tank and pooling and dripping from the sending unit.

just something you might check.....

shane

original sender and retaining ring or aftermarket?

I have found the aftermaket retainers to be flimsy and actually distort causing them to slide off center.

also the raised or stepped portion of the sending unit helps center the assembly on the ring, this step is shallower on some of the repos, making it tricky to keep everything centered when securing it.

I used to always use a brass punch, but with the thinner stuff I have had more sucess with the correct tool, OEM retaining ring, and pulling the tank to be certain everything remains centered when tightening.