Help needed with fuel issue

[VA72C10]

UPDATE:
I pulled the line coming in to the fuel pump and the gas immediately poured out. Luckily had my gas can there to catch it all (good to plan ahead sometimes) It filled up the 2 gallons (figured I'd put it back in and make sure I knew how much I had)

I'm guessing if the fuel is flowing (and looked decently clear) that that narrows it down to the fuel pump? I plan on going to the parts store this afternoon to pick a new one up. If it could be something else feel free to let me know



Original post
On my 69 shortbed I'm selling, I was going to drive it today to keep it running good for the next owner. It has always been hard to start, but ran like a top once started. Today, It will only start w/ gas added directly to the carb. It runs a few seconds until the gas runs out. It has one of the clear fuel filters on it (Has been on there for years from what I was told) I changed the filter today to see if that was an issue. No gas is coming through the filter at all. Obviously this is why it cuts off and won't start w/out adding gas to the carb. I know that there was/is bad gas in the tank from sitting. I have added a gallon of new gas but done nothing with the tank. I am guessing that the filter at the sender is clogged or that the fuel pump is bad. Anything to try before I pull the sending unit? Is there a way to check if it's the fuel pump? Would I be getting any gas pulled through the fuel pump even if it was bad w/ the engine running?

When it runs there is no smoke and it runs smooth and pretty strong for a stock engine. It ran just before I parked it a few weeks ago (but had to add gas to get it to start last time as well----only that time it continued to run once it started.)

If I do have to pull the sending unit, is there a way to move the stock bench forward enough to get to it w/out taking the bench all the way out?

Thanks for any help!