Starts after hearing a pop coming from the fuel tank

Do you hear the pop with the gas cap off or on? Does it start immediately after the pop or do you turn off the key and then it starts? Off hand it sounds like a sticking fuel selector solenoid. What is likely is that because you are not using both tanks the valve is not moving free and is settling as the fuel pressure bleeds off overnight. Now you turn the key, the pump has to build pressure enough to open the valve as the solenoids default to the front tank. Try cycling the switch a few times to move the solenoid spools and maybe free them up. Or if you do not intend on using the front tank, go under the truck and bypass the selector valve.

Yeah, the cold makes the plastic parts of the switch contract and stick. We had an ambulance in the shop that, when it got cold you could not switch tanks, it had a 460 that loved gas. Not being able to switch tanks was not good.

Here is what it looks like. Located inside the frame rail almost in line with the front fuel tank filler.

OK looking at Fords own info. They used the external selector on trucks up to 89, then switched to a different style but your truck could have the internal FDM depending on the tanks used. Sorry about the mix up. Looks like some of the "factory" info is confused.