Sorry for reviving this thread. I just need immediate help. Hope you understand.

I owned a Crossfire 4.6 liter that was running a little rough yesterday and it died on me a few times. Today it started rough, I pulled it out of the garage to change the oil and the oil coolant lines. Upon completion of the oil change I attempted to start it and no ignition. It cranked fine just no start up. I put about ½-oz of fuel directly in the TBI and cranked and it started and then quickly died. I replaced the fuel filter to be sure and while I had the filter off, I cranked the engine and there was no flow of fuel. I am pretty sure it is the pump, is there any way to test it or was my test adequate. This vehicle has 144,900 mile on it. I replaced the engine in the past with a factory GM crate engine. I think the fuel pump is original. To replace the pump do you know if there is an access panel or do I have to drop the tank?Also i am planning to replace it. Anyone here knows to replace fuel tank?