If we go by the story the manger is what he sleeps in which is a feed trough for animals. I'd use 1 X 3 furring strips. Make 2 X's and then cut some slats for the top outside of the X's to connect them together. Add some hay and done I'd think. Depending on how it's facing could make the legs on the street side a bit shorter (or prop up the back) to add some lean so passers by could easily see the blow mold?
Shaped kind of like You are not allowed to view links.
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