Shaving mice must be a suck job.I think you will find that the thickness of the headliner is not the issue for mounting things to it. At least on my 2003 the headliner appears to be composed of an alloy of compressed mouse fur and recyled dryer lint, bonded to that gray fabric that adorns the roof over your head. Once you puncture or cut it, it will return to its native state. It has no ability to hold a screw or other fastener. You might use a backing plate to spread the load over a larger area, but the better approach would be to fasten a bracket to the metal frame above the windshield. The sun visors are attached to brackets fastened in that manner. Take a visor off (4 torx head screws) and you will see the bracket behind a factory-formed hole in the headliner. If you cut a similar hole for your mounting you will need to devise a way to seal the edges. A prior owner of my van mounted speakers in the headliner. I ended up making backing rings out of 1/4 marine plywood in the hopes of making them stay in place. So far it is working, but I would not recommend mounting speakers in this manner. (Speaker magnets are heavy.) One thing that you learn as you get older: In the end, gravity always wins.
Good luck.
Its better than milking mice.Shaving mice must be a suck job.
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