Fuel pump on a 2001 BMW 325xi on 2001 BMW 325xi

I'm pretty sure my fuel pump went out on my 2001 BMW 325xi. Can anyone tell me where it's located. Is it under my passenger side rear seat or in the tank? How difficult is it to replace?

Asked by for the 2001 BMW 325xi
in the gas tank, you can replace just the pump w/o having to replace the entire float assembly
1 more answer
I think it's in the gas tank :(