On the older AWDs, no such door exists like it does on FWDs or older RWDs, they didn't include one with AWDs, at least the early years like yours. If the fuel pump has to be replaced, the rear exhaust, rear axle assembly must first be lowered, then the gas tank. It's a very time consuming process that no one enjoys doing.
Fuel pumps are often noisy on AWDs and if you're out of warranty, I'd just turn up the radio rather than pay the required labor to replace it.