How do you change fuel pump on 1999 Mazda millenia?

I tried replacing a Fuel pump on a 2000 Mazda Millenia. There are there openings total. Two (2) of the openings are under the back side passenger seat. They two shiny plates secured with 4 screws each. They are NOT for the fuel pump. They are for fuel LEVEL sending unit(Fuel gauge)In between the back rest, there is an opening which opens to the trunk. Take this "plate" out and there is the fuel FILTER and pump. Due to limited space I was not able to take the FUEL PUMP OUT. I gave up!!!! The fuel tank has to come down!!!!