Trying to get long-unused S10 Blazer Running

This 1985 S10 Blazer 2.8L V6 was bought new by my father and later owned by my late brother who died six years ago. It was partly disassembled at the time of his death, and it sat unused until last year when I started the project of getting it running again.

Long story short, I did everything I could think of or read about to get this car started safely: new fluids, drained gas tank, turned engine by hand first, etc... It would run briefly with gas or starting fluid in the manifold but wouldn't stay running. I had the carburetor rebuilt, which it definitely needed, and reinstalled it yesterday (Varajet 2SE). This car has a mechanical block-mounted fuel pump, not an electronic one in the tank.

Since I was worried about sediment in the gas tank, I primed the carburetor float chamber with brand-new gas and routed the mechanical fuel pump intake into a separate gas container with the same brand-new gas. The car started and ran normally for about 30-45 seconds and then stopped. The line I was using for gas is clear plastic, and no gas was drawn up into it towards the fuel pump.

So now I'm thinking the fuel pump is bad, too.

Any tips, especially on replacing the fuel pump on this 4WD 2.8L V6? One of the bolts that holds it to the engine block looks pretty hard to get to.

Do fuel pumps go bad just from sitting? My brother was working on the car's headlights when he died, and there were problems with the lamp connectors, which I've fixed. As far as a friend of his knows, this Blazer was running when my brother died, but wouldn't pass inspection due to the headlight problem.

To follow up, I got advice elsewhere suggesting that with the whole fuel system completely dry, a mechanical fuel pump may not be able to self-prime and draw gasoline up from a container at ground level. They suggested I might need to prime the pump with something like a fuel priming bulb you'd use on a boat.

A three-line fuel pump should be able to draw fuel "uphill" from the tank, but it may need to get the check valves wet with some fuel before it can do it consistenly. The marine primer bulb is not a bad idea, but none of those were ever rated for any heat, so it should only be temporary and then be removed so the original line configuration can be reconnected.

Have you tried blowing backward through the fuel pickup line to the tank (with the fuel cap removed) to see if the pickup sock filter in the tank is plugged with sediment?

Update: I got the new fuel tank installed.

I was able to prime the fuel lines, fuel pump, and carburetor with a marine-style bulb.

Now on to other problems.

Progress, at least.