David,
I cannot find a template or instructions for installing the 54/55 interior mirror.
Here is what I have done on two trucks:
- With the windshield and headliner installed, position the mirror arm above the windshield, above/adacent-to the windshield seal, above the middle of the window.
- Marked the two hole locations.
- Drill through the headliner and the first layer of sheet metal.
- Attach the mirror arm (two screws).
I have a cab stripped and could post a photo, so that you can see what you would be drilling through (just ask).
