Ok Scotty, take it to warp speed 2 cup.
It had over 24hr started to work, but rust not completely removed so I have now a second put cup into the original mix. If that works quicker I will find something else rusty (which I have plenty of….) and prove the speed of removal.
Interesting some black rattle-can flakes in the water. Was that just loose, or where some rust had sat underneath. The factory blue does not seem affected.
24hr 1 cup in 15lt
24hr 1 cup in 15lt