It sounds like you have a lot of experience with marine diesels.

I agree to pull off the bottom of the tank. I do this by putting a section of copper tube in the end of a plastic tube so it sinks to the bottom.

After pulling all the water out that the hose will pick up I would put in a few cans of antifreeze for diesels and put in five gallons of fresh diesel and head for the nearest station and fill up. Then I would keep an eye on the filter and othewise not worry if the engine ran fine at that point.

I am not sure all your marine experience translates directly to automotive situations.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.