I'm not sure how would achieve this. Cut away the part entirely and epoxy the 3D printed part in its place?
Anyway, I wouldn't bother. Most of mine are cracked. It was poorly designed in the first place. The shroud doesn't usually sit flush at the bottom, so the overhanging part will, well, hang in the air. Tightening a screw through it will put stress on it and eventually crack it.