I know this is an old thread, but does OP (or anyone) know the best way to determine the location on the floor to cut an access hatch? I have a jacked-up rotator cuff at the moment that makes twisting, lifting, etc. painful. I've done a similar thing on a Jaguar XJ6, cutting a hatch on the rear window parcel shelf with an angle grinder, to get to its upright tank behind the back seat.

Blazer is '97, 4-door, 2wd, automatic, steel tank
Fuse and relays (all 3) check out as operational. Don't hear any pump hum switching to "run" & get no pressure at port in engine bay, but it will start and run for a second with a shot of starter fluid.
So, fuel pump, right?
One other odd thing, not sure if it has any bearing: The fuel gauge sits at about 1/3 tank when off. Turning key to "run", the fuel gauge needle fans wildly left to right and back a few times, then settles to empty. Turning the key off, the gauge moves to about 1/4, sits there a few seconds, and then moves to 1/3.

Also passing along to any who might stumble across this later, since I ran across a lot of inaccurate stuff (at least for my car/model/year), some even from "experts", while searching:
Fuse location is NOT under the dash. It's in an easily accessed panel on the left end (driver side) of the dash. You have to open the driver door to see it.
I'm not sure which relay is for the pump, but it's not the center one of the three...that one does the horn.
The relays are IN the glove box (not behind it, or under it), at the back, behind a cover that says "relay access", of all things. Use a flat screwdriver to push up the two hard to see bottom tabs of the cover, and then slide the cover to the right to release the top two tabs.

Thanks for any help!
EDIT:
Found this thread with pics of the floor cut. I think I can figure out the location by referencing it to the seatbelt anchor bolt shown. Seems like he cut it a bit wider than needed, though.

 

cut it where theres a high flat spot, along the top of the ridges in the bed, that makes an easier job of resealing the cuts.

I can measure my S10 pickup if that would help.

My ' cut the bed' job was from living in an apartment complex where I couldnt pull the tank...

Id be tempted to go to an external pump...the new Delco assembly I bot about 10 years ago was $400...