Truck is slowly breaking down on cross-country trip, help!

[Xavier]

Hey guys, my '68 C20 with a 327 and manual 4-speed is giving me multiple problems. I was planning on towing the truck across country but last minute plan changes forced me into driving it without having time to properly prep it.

Symptoms started with a misfire, likely due to the plug wires cooking on the headers. I attempted to buy replacement wires en route but I neglected to get a set for an HEI setup (Delco Remy) and just ordered them by year/make/model so I obviously ended up with wires intended for points. I was able to get the correct wires the next day but that didn't change the miss at all. I had a brain fart and forgot to change the plugs at the same time.

After about 1,200 miles I started experiencing what seems like a fuel starvation issue. I would be going down the highway and the truck would start to sputter and buck until I let up on the throttle. I could then lightly press the throttle to maintain speed but anything more or hitting an incline would bring back the sputter. I limped like this for over 100 miles before stopping for fuel. After the re-fuel it ran like a champ... for about 20 miles. Then the starvation symptoms returned. I couldn't source a fuel sender locally but I did replace the in-line fuel filter and the mechanical pump. I opened all the lines from carb to tank and blew them out, there wasn't really much in them. I know the sender doesn't have a sock on it and my tank is rusty but I was able to drive another 700 miles today before the starvation symptom popped back up.

Looking for some advice on what to look at because I still have another half of the country to cross.