I had been having increasing issues with the truck stumbling and hesitating when the throttle was applied, and I've finally solved it. It dawned on me after awhile that it might have been a fuel pressure problem, and when I noticed that it was particular to the front fuel tank, I obviously began to suspect the fuel pump. It was confirmed when I noticed that the front tank was filling up with gas while I was using the back tank. There's a valve inside the two port tanks that allows the fuel being pumped from that tank to return to the same tank, which saves on extra valves and so forth. It's as simple as having a single fuel and single return line for both tanks, with no electric valve in the middle. That valve must have been sticking open to some degree, so after replacing the fuel pump things work like a champ. One of the few things about Ford products that drive me absolutely nuts is those damn fuel line connectors. I have a set of those little plastic tools that release the retainer, but they sucked so bad I had to partially drop the half full tank to be able to get at the upper connection well enough to remove it. Royally frustrating, especially when my shoulders are shot to hell.
Thought I'd pass that on for those who will need to know eventually.