Alright so problem solved it seems…
I dropped the tank and immediately noticed the sort of caked dirt around the dust cover and ring. It certainly looked as if fuel had made its way out and dried, as I suspected when i saw it with the boroscope.
I cleaned the area thoroughly with a brush and compressed air then removed the ring and lifted the dust cover and noticed the gasket had some caked on mess. This, i believe, would have been caused by fuel meeting dirt. Had the gasket been working properly, the dirt and the fuel would never have made contact.
This all sort of corroborates the the theory the seal between the dust cover and tank wasn’t good.
I cleaned the surface of the dust cover and the tank where the gasket seats, and placed the dust cover back on using a new OE LR gasket.
Once the tank was back in, I started the truck, cleared the trouble code, and it didn’t return (it was returning right away for the last few weeks).
Let it run for about 20 mins, seems to be running a tiny bit smoother and idling a tiny bit higher.
Fingers crossed that is that.
I didn’t replace the fuel pump. I ordered one but after two days it hadn’t shipped despite me paying $40 for next day delivery. I took it as a sign.
Few tools I purchased to make this job a lot easier… a gas tank lock ring wrench. I bought the $16 universal one on Amazon. I wasn’t going to pay $80+ for a one-time-use tool from one of the LR specific sites. As much as I despise Amazon and want to support independent businesses, i have my limits and the price of that tool is pointlessly dumb. I also purchased a transmission jack to lower and raise the tank.
Now I just need to fix the leak I just noticed from the rear crossover pipe.
Like they say… One Life. Live it… in the garage looking for strange leaks and weird sounds
Few pics of the gasket mentioned and the new gasket: