Evapo Rust Yellow Residue

[SGM Dan]

Evapo Rust leaves a yellow residue on the metal in my gas tank. I don't have access to wire brush it off. How can I neutralize this inside the tank and behind the baffles in order to prepare it for tank sealer such as POR 15? I've contacted Evapo Rust several times to talk with their engineers or a knowledgeable individual at the company, apparently there are any! They've ignored my emails, won't call me back and simple won't answer for almost two weeks now. Terrible customer service!

 

[Kevm]

I have never used evaporust but I know you need to have the tank really clean and free of any surface film before you use POR15.
If the evaporust has done it's stuff and removed the rust can you wash it out with some water and detergent then dry it with the airline and hot air gun.
Or you could lash out on some POR marine clean.