Can I change the sights on my Beretta APX [Optics Ready] at home?
Yes, with a sight pusher or a punch. Drift the old sight out of the dovetail and push the new one in. If you do not have the tool, a gunsmith can do it for you.
Do these sights fit both the classic and the Optics Ready variant?
No. They do not fit the classic (non-OR) variants.