Retrofit Volvo V60 B&W

[dawn_s]

I'm preparing to do a more humble version of this upgrade (Base to HK) on my 22' XC60 and was wondering if anyone could answer some questions for me.

As of now, I have:
- A HK AMP from another XC60
- A full set of HK speakers from another XC60
- The HK grill for the center channel
- Speaker grills for the headliner
- Some extra pins and connectors for adding the extra outputs from the AMP
- Wiring harnesses to scrap the male speaker connectors for the headliner and subwoofer from.

Now, my questions and uncertainty:

1. What kind of fasteners do I need to physically mount the speakers that I don't currently have, like the headliner speakers and extra door speakers?
2. Is there an optimal technique for pulling down the headliner to cut the required holes?
3. Is there an ideal path to route the missing wires for the headliner speakers and subwoofer?
4. Am I missing anything from my list above?

Trying to avoid ripping my car apart and then needing to drive to a hardware store mid-job for a bunch of screws :3

Thanks!