I'll tell you what immediately solved the issue I was having with surging and sputtering after I switched to the front tank.
(RISLONE
Diesel Fuel System Treatment (4740)) Complete Fuel system Cleaner
https://rislone.com/product/diesel-fuel-system-treatment-4740/
The next day, I didn't do any of the diagnostics I had mentioned, didn't check anything. I started the truck on the front tank. It sounded a little rough and after about 5 seconds the engine died. I think the outdoor temp. was 40 deg. F (4.4 deg. C)
I restarted it, kept it running this time by depressing the accelerator pedal a little bit for more fuel to keep it from stalling again and after about 10-15 seconds it would hold a fast idle. I always wait about 15+ seconds after the oil pressure comes up before I start driving and drive easy until the temperature gauge starts moving up past the low line to maybe half way to it's normal operating temperature.
I drove on the front tank to my credit union to get some money and back home. It was still running rough. The bottle of fuel system treatment, including an algaecide that I had in my shed was almost empty, maybe 1/2 cup left. I put that in the front tank and then drove to get fuel. Filled the rear tank and topped off the front tank which took 4 gallons. I think that is a 19 gallon tank, rear tank 16 gallons.
Then I drove a couple of miles to a parts store where I bought the bottle of RISLONE, enough to treat 30-35 gallons and a bottle of "CLEAR-DIESEL" 'Fuel and Tank Cleaner' by POWER SERVICE enough to treat 100 gallons:
https://powerservice.com/psp_product/clear-diesel-fuel-tank-cleaner/ an interesting note on that page:
Water has always been a problem in diesel fuel. But today’s cleaner-burning fuels have dramatically reduced sulfur content and are more prone to water separation, contamination and are inherently unstable.
I put almost the whole bottle of Rislone in the front tank. Even though it has a convenient spout that also fit on the Power Service container you can't tell how much is going into the tank without using a funnel. I put the small amount of Rislone that was left into the rear tank and too much of the Power Service product but that wont hurt it.
I started the truck and it very quickly ran better,. very well with no issues. In fact it ran so well that by the time I had made a couple of stops and restarts, from the first one, my fast idle and curb idle had increased by 100 RPM. The injector noise had also noticeably decreased. My only explanation for the increased RPM is that the injectors were cleaned and the reduced clatter is from some extra lubrication and cleaning of the injectors.
I would expect a similar fuel treatment to help your situation because, I believe that in South Carolina you have had some unusual weather during the past year or two, with that extreme rains and flooding plus some unusually cold weather. The colder weather increases the condensation in the fuel tanks and might be part of the reason for the hole in the front tank (internal rust)
Contaminated fuel could be the whole cause of your issue or at least part of it and I would highly recommend adding a good fuel system treatment to that tank. My choices were made by comparing the labels on the products at local parts store and I didn't buy the highest priced ones.