so this is definitely going to be the cheapest and jankiest option, but you can basically implement it instantly.
buy a digital outlet timer and schedule it to be on from 03:01 am - 02:59am. The router will lose power for 2 minutes at 3am in the cabin, but it will get rebooted every day.
but i can tell you this is an industry standard enterprise approach to this type of issue.

If you don't feel comfortable fixing it where you are, search for a maker space. libraries in larger cities often have a maker space where you can get tools and expertise to complete these sorts of tasks. They may even be able to connect you with people willing to help for free. It's highly unlikely that you will break your computer by replacing the thermal paste on the video card just ground yourself by touching a door knob or faucet before working on the system and don't shuffle your feet on carpet in between the door knob and your workspace. That should eliminate most static shock which could cause damage to your circuits.