Belts behind seats on BB?

Hi, what is the purpose of the leather belts behind the seats in the BB? Was it to hold some thin luggage in place (and was there BB luggage offered at that time)?

How can they be removed for refurbishing? Looks like the tops are riveted in place so maybe drilling out the rivets? Bottoms are screwed in if I'm not mistaken.

Thank you!

 

Amazing, do these ever come up for sale?

Answered my own question:

https://bringatrailer.com/listing/ferrari-512-bb-luggage/

 

Any thought from anyone on how the belts are removed? Drilling the rivet at the top will result in the other side to fall into the nowhere of the car?

Thanks!