@lg2688 May I ask why they need to be gone right now? If the reason is financial, you will need to talk to his doctors about someone in the family getting a durable power of attorney to do it. Be prepared for lasting anger about it.
If the reason is space, can you store them somewhere, either on land someone in the family has, or in rental space? Then if he needs to see/touch them to make sure they are still his, take him there.
Another thought - can you offer a reward for letting them go? Use some of the money to take a short trip, go to see a favorite team play or buy a big screen TV for watching his favorite shows?

PS Years ago, when my Mom was no longer safe to drive, it fell to me to get her evaluated, take her driver's license, and sell her car. I then became one of her main caregivers for over 5 years. A few days before she died in hospice, she told me "I never forgave you for taking my car away." So the anger may be long lasting.