Why do you want to go through all the trouble of dropping the tank? Remove the bolts that hold down the bed. Get some help to tilt the bed back (looks like a dumptruck). You can then remove the wiring harness connector for the rear lights, then disconnect the fuel lines. Removing the bed allows total access without the drain and drop problem. You can have total access to the pump lock retainer and replace the pump. An easy way to raise the bed is a ratchet strap under a tree, but be sure to brace with a 2x4 for extra safety. Install the the pump and reconnect everything, and lower the bed and replace bolts. Guess what you are done after starting the pump a few seconds to recharge the system.

 

I have a 00 chevy tahoe LS 5.3 I am doing the fuel pump and cannot find where A line broke off the two main lines going to the fuel pump are ok but there is a nother line that broke off that kind of goes near the transmission area does anybody know where to find this and is it important it kind of has a u-shape at the end of it and is away from the lines that go to the fuel pump