Powder coat can be removed with socking in the nastiest paint remover you can find.
None of that citriastrip crap... you need something that warns of ventilation and cancer causing chemicals to do a number on that stuff.

IIRC; I had good luck with
P_20200522_014718 (resized).jpgP_20200522_014730 (resized).jpg
Believe I got it at Lowes in the paint isle.

And yes; this stuff is so toxic it "inflates" it's own container and leaks.
This is the type stuff you need to use gloves with as it will burn your skin. You need the chemical gloves for this stuff. No latex or nitride as they don't hold up for more than a few seconds against this stuff.

I've seen reports of "aircraft paint stripper"; but I've never been able to find it easily.