So i purchased a remote switch relay that has a 12v input, and two connections to open and close 1 wire.

After looking through the Haynes manual, I discovered the wiring diagram for the EFI, COR, and other related components. According to the diagram, unless I'm reading it wrong, shows a blue wire, and a white with black wire that should be directly connected to the fuel pump. This should be the COR pictured below. There's no mention in the wiring diagram in the Haynes manual of a Black with White Stripe wire, just a White with Black stripe wire.

Since interrupting continuity in the blue wire with my switch did nothing, will using the white with back stripe wire work? Not really looking forward to taking the dash apart again, but its gotta be done anyway. While swapping to a newer dash, I forgot to swap out a portion of my air ducts. Oops. Big hole in the passenger side where a vent should be lol.

Here's a photo of the section in the Haynes manual I'm referring to (section 12-17)

 

Unfortunately the wiring on my truck is a little bit different. Mine is attached to a black and red wire that is in the same spot that your blue wire is in. Since positive voltage flows through that junction block your best bed is to activate the fuel pump with the truck in the on position and not running and testing each wire individually for voltage with the fuel pump both on and off to find which wire it is