Busted Brake Cover

So this past weekend, I was hooking up the "new" JD #5 mowers I picked up to my M (thanks for the help on figuring that out as well!) and I had to crawl around underneath it to remove the swinging drawbar. While I was under there, I noticed that the brake cover on the left side of the tractor had an adjuster bolt on the bottom, but the one on the right side only had a large gaping hole in it.

So, my questions at this point are:

1. What does this bolt even do? Is it important to the brake system at all?
2. Im guessing there isnt an easy way to fix this with the existing cover... Is there?

Thanks in advance!

~Bug

I guess Ill go try to tinker with it and see what I can come up with. I have a feeling that Im going to need to replace the bands before too long as it stands, but I havent torn into them yet because I know once I start, Ill have to keep going....