Help: Engine swap

[hoot972]

Just switched a 1998 cheyenne 4.3 vortec to a 2002 4.3 vortec. Low fuel pressure. Can turn key on and off several times to prime, starts and runs for a moment. Seems like fuel pump to me but it was fine before swap. Amazing how that can be. Any ideas before i replace the pump, is there maybe some difference between the 1998 and 2002 like fuel pressure. Also i was told if i unbolt one shock and jack it up and remove one strap off tank it will drop down enough to replace pump. Is that true? Any help or ideas? Thanks

[mudrunner80]

I'm having a fuel issue too but as for getting access to the pump ,the easiest route to go is remove the bed. atleast enough to replace it.