where in gods given left leg is the in tank filter and when you open and remove the fuel pump to change it do you also have to replace that o-ring underneath

You should replace the O-ring when you do this since it is right there. You pull out the fuel pump/filter assembly from below the rear seat. The fuel filter is located inside the plastic cylinder-type thing at the bottom. Take your time and make sure everything goes back together how it should and thats about it.

i wa there looking at that today, now i know there is 3 clips holding the plastic thingy together but what else because i couldnt seem to get it apart.

oo and do youknwo what the autoparts store name for that o-ring is? and thank you youare god

I doubt you'll be able to find it at any parts store. Call Dave Burnette at South Point Nissan and he can get that for you for a great price. His number is in the FAQs.