In vanilla game, the door collision in Diaz mansion is made out of two boxes, but they were not placed on the sides of the doors, which makes it possible to clip through these holes inside the mansion before it's officially allowed, which is used to quickly pass the Rub Out mission. This modification redesigns this collision, making it into a surrounding mesh for doors, making it impossible, or at the very least much more difficult, to get through. The collisions of the open and closed door have been changed.
2 methods of installation are provided:
Easy Method: mansion.col from "Easy Installation" is either moved to the modloader folder, or replaced in gta3.img using img editors.
Advanced Method: mansion.col is extracted from gta3.img (or from modloader folder where mansion.col is replaced), then using col-files editor man_doorclosed and man_dooropen are replaced with the ones in "Hard Installation" folder and then resulting mansion.col file is installed similar to the simple way.