HEY !!!! That's a really good addition to the design... If you don't mind me using it, I think I'll remove the bolts and put studs upward with wing nuts for quick / easy "freeze" tank changes... I have not bought the plate yet, but my idea was 3/16" for the "freeze" tanks and 3/8" for the coolant tank...

Now, learning how to TIG weld aluminum without LEAKS !!!