I installed a set of Ameriglo classics on my G19 today. The rear sight was extremely tight, to the point where I thought the Glock Sight pusher would seize up. I backed the sight out and filed just enough to knock the finish off. The second try was better, but still really tight. After another touch up with the file they fit nicely, still extremely tight using the tool, but not to the point where it felt like they were binding or the tool would break. My question is about rust. Should I remove the sight and touch up the bare metal with cold blue or some other finish or leave it as is and not worry about it? I realize rust isn't really a big issue with Glocks, but I'm not sure about the sights rusting and possibly ruining the slide. I'll have access to the sight pusher later this week if I should need to remove them and touch it up, but if it isn't needed, i'll not waste my time and/or possibly mess up the sight. Thanks in advance...