I checked the Chevy dealer on the part, and only the entire partition is sold - for $250 (as low as $125 via the internet).  I can get the partition to stay in place if I put it there and brace something against it, and I'm sure I could keep the button secured if I put some black electrical tape over it, but I would prefer to have a better fix (but not at $100 or more!).

 

Anyone else have a similar problem and have a good fix?

 

Thanks

 

I was able to separate the two sides of the grommet on the driver's side and my plan was to replace it to the passenger side so it would hold and keep the switch depressed.  Well, that worked to a point.  But when I then tried to remove the partition from the pins, the grommet again came apart and the part that holds the switch in place stayed on the pin, permanently depressing the button.

 

So now I don't have to worry about not being able to put the top down, but I do now need to figure out how to hold the partition up when I do have anything of substantial size in the trunk when the top will go down.