Using Evapo-Rust to remove rust from calipers - can I submerge them?

[eljay]

I picked up some used B7 brake calipers. The fronts have some surface on them and the rears are quite bad when it comes to rust.
So, I thought I could just try to scrape of any loose rust from them using a brush and then submerge them into a bucket full of Evapo-Rust and let them soak for a few days.
I do plan to get new dust boot and seals for the pistons, so I'm not concerned about damaging the old rubber, as I plan to remove the pistons etc.

But I'd like to know whether this is safe to do, to submerge them into Evaporust like this.

After removing the rust, I'd like to paint them, then re-assemble with new seals/boots.

Thank you.

[eljay]

Anyone?
I'm just wondering whether letting the Evaporust inside the caliper (via the opening where the brake line will be connected) will cause any long-term harm once it's filled with brake fluid.