GM chassis's also has fuel pump in tank.
Check under dash fuse panel for fuse.
Should have fuel pump relay. It is located on left side of engine compartment on brace. It should energize for about 10 seconds when key is turned on, then drops out.
Fuel pump power is routed through the oil pressure sending unit. Mounted on left side of engine toward the front at bottom of block. It supplies power when the engine gets oil pressure.
What chassis do you have? Ford or Chev?