Ok. I'm new around here, but not to forums in general. I tried the search, but got limited results. So I'll try here. I'll try to give a back story & describe my problem as short as I can, but it will be lengthy.I have recently purchased an 84 chevy pickup, long bed fleetside, 305--dual fuel tanks. This truck has spent the last 12 years parked at the edge of a cow pasture. The previous owner said they parked it due to a carburetor problem that could not be remedied. It originally came with NO carburetor on it. So, I put a different carburetor on it (Quadrajet) that I had from a previous pickup. Sooo, here's the problem I found. Truck will sit & idle in the driveway all day & purr like a kitten. Get it out on the road, it runs good- until you step into it to pull a hill or anything requiring moderate to heavy throttle. It starts out good, but quickly starts to sputter & will die if you stay in it. It will recover if you back out of it. If you let it die, pull it over, pop the hood, the fuel filter is dry. Let it sit a few mins, crank it a bit, it will fire & there will be fuel in the filter, & it will run & drive as long as you don't get heavy on the gas pedal. So, now what I have done already to try to remedy the problem. I aquired the original carb from the previous owner, tried it- same problem. So, I believe it is not a carb issue like they thought. Next thought- fuel filters. Replaced the small one in the carb body, also replaced the screens in the glass aftermarket one mounted just before the carb. Same problem. There are no other in line filters. Next up- mechanical fuel pump. 12 years in a field can't be good for a $20 fuel pump, right? So I replaced it. Same problem. Next thought- sending unit socks clogged. Pulled both tanks- tanks have no rust, socks flow as they should. While pulling tanks, replaced all rubber fuel lines between fuel tanks & selector valve to fix any cracking, collapsing, or dry rotting possibilities. Also blew air through all metal fuel lines both with a compressor and by mouth to determine any restrictions. No restrictions found in any of them. Feeds, returns, or vapor lines. The only thing I found that restricted at all was the selector valve itsself. Now, this valve does work, it switches tanks, the gauge switches accordingly. But the same problem still persists. So, the only thing left at this point is the tank selector switch, & the selector valve. They are the only 2 pieces left original at this point. But before I dump another $100 chasing this elusive gas ghost, I wanted to ask opinions here to see if anybody has traveled this road before me, & could offer some advice. Thanks in advance for any help offered!!