10 minutes of success, followed by the roughest ride home.

[Cuatro]

Happy holidays everyone!

I'm new to the forum, but excited to get some assistance from people who truly appreciate what we have. My rebuild is Elvis. He's a '65 fleetside long bed with the straight 6 292. I have had him for 3 years, but sadly only just got the chance to really start getting work put in. I purchased him from a mechanic at the auto shop at my last base who told me the truck was running, just needed a new battery and some work on the lights. Definitely not the case, but I've almost got it going. My main issue right now (lighting aside) is that I can make it flawlessly about 5-7 miles down the road. But, when I turn around to go home he starts choking down like he's out of gas. New carb. New fuel filter. No leaks anywhere. And once he cools back down, runs fine until another few miles then repeat. I'm an aircraft mechanic, but new to vehicles aside from the basics. Who has some advice?