My '97 Z28 burned up its fuel pump after the fuel filter became clogged.
(long story)
Let me say this to start, this is not a fun job to do.
After spending many hours removing the heat shields and exhaust (3" catback flowmaster set-up) I could not get the gas tank to drop! The subframe was in the way. I removed the lateral stabilizer/torsion bar as well, but the tank still would not come out because the neck lacked the clearance.

Here is how I fixed it:
I cut the neck of the gas tank (just after the flex bumps) and used a radiator hose to reconnect the pieces. This is the first gas tank I have seen that the neck is 100% solid to the tank. Why did Chevy do this? (Rhetorical)

I thought about the trap door for the fuel pump, but the connections for the lines coming from the fuel pump are on the back side of the tank. So, I'd end up having to get the tank out anyway, which was my whole problem.

More words of wisdom, get a torch if you are messing with exhaust!

 

If I ever have to replace my fuel pump, I'm cutting through the floor board to get access to the fuel pump.