water in fuel

in my rear tank it has water in it and i filled the tank completely up and put lucas fuel treatment in it and that didnt help so what other fuel treatment could i use because i really dont wanna drain a completely full tank of fuel and dont even know howd id go about that???

Let it set for a while. Water will settle to the bottom (it is heavier than diesel). Pull the fuel line off the filter, drain it into a glass container (that way you can see when it changes from water to diesel. Replace the fuel line. You can get some water absorbers at truck stops. Throw some of that in afterwards.

How will draining the filter bowl get the water out of the tank? Won't s/he have to crank the engine (IDI would have a mechanical lift pump, IIRC) with a line from the rear tank going into a collection vessel to get that settled water out?

But yeah, waiting 'til the heavier water settles to the bottom is the key.

Get a little 25 dollar electric fuel pump from the parts house. Where there is a will, there is a way.