Making holes 3

Fig 1: Identifying Edges To File

Courtesy of VOLVO CARS OF NORTH AMERICA.

NOTE:
It is very important that you use a marker light to make sure that there is no play in the hole before filing out the marked borders.If too much material is filed away, the door must be replaced .
File away the material so that the marker light can be fit without problem, but do not file away so much that it is loose.
File sharp edges.
The hole making principle applies even though a rear door could be hidden.