Today I did manage to get down there and make some pretty good progress. I cut and installed all of the backdrops for the middle level. I also went ahead and redid a bunch of the screws holding up the backdrops on the lower level that were not countersunk deep enough. I originally thought that having the screw heads flush with the Masonite would suffice, but after finishing a few screw holes with joint compound, I realized that the screw heads had to be sunk just as if I was installing drywall. I'll do a special post in the next few weeks detailing how I am finishing the seams between the sections of Masonite.
Here are a handful of pictures showing the new middle level backdrops:





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