They aren't difficult to install, just tedious to fit.
They block the striker, which I'm sure you already know and sometimes the striker doesn't sit back far enough for the indent to engage.
The striker can be modified in that area so the indent will engage and block it
Only remove metal where the safety indent will engage.
Otherwise you will just get the same problem again, because the striker extrusion comes up against the face of the sear, which determines where it's going to stop.
