Yeah sorry.
In this case, these are old Rockwell Coach brakes. There isn't a dust cover and you can directly see the shoes from under the bus. Unfortunately, they are mostly blocked by this train-like frame that holds the rear differential and the 4 air shocks that hold the coach itself.
When I say we pounded on them with a 2ft rod and a sledgehammer that was directly on the shoes themselves and they didn't budge. With everything fully aired up and the brakes disengaged.
It took an air hammer on the side of the shoes directly to get them loose and then only one of them because we couldn't get a clear site of the other shoe.
To address another comment removing the tires is a major undertaking that I don't have to tools to do and doesn't actually provide much more access to the shoes. Just a nicer place to stand while working.
The issue is not snow, but starting that big cold diesel in the cold. It doesn't have glow plugs and starts by pure compression. I don't have a block heater installed. It originally had a Webasto heater that didn't work, I ended up removing that and selling it on ebay for a couple thousand $$. It also had a 4-cyl Kubota diesel pony engine that ran the old coach AC units that I sold and that covered a good fraction of my original purchase price and gave me space for a storage locker.