Same issue - if the wiring is getting hot enough to catch a sock on fire, it would burn through the housing since it is made of plastic, and could catch the rest of the car on fire. I still wouldn't use a sock, but it should be fine if you want to take that route.

Big Mack

 

you can PROBABLY remove the housing of the brake light and the brake light may still work fine. it might look funny but better than a towel. orrr, you can remove the third brake light all together. you dont need it...

 

I put a chunk of foam down there, and will report back a little later to see if it solves the problem.

Thanks for all the responses!!!