Making patterns of the walls & papering over acidfree cardstock is a good
idea even if you just want to change the decor later. You could attach the
wall pieces with double-lided tapethat would hold everything close enough to
the tape run so the brads make contact.
"Cathy Weeks" wrote
I had an idea about wallpapering - it's going to be difficult working
in such enclosed spaces ... what if I made posterboard plans of the walls,
made sure
they fit perfectly, wallpapered that, and then when it was dry,
affixing it in place, perhaps with wallpaper paste.