In Snapshot 18w50a placing skulls that have an overlay (hat brim, mask, etc.) it gets put in weird ways unless it is facing north. For example if it is facing south the hat brim is mirrored underneath the skull. If facing either west or east the overlay is on the side something liek setting a book next to another book.

I have also noticed that placing skulls at a diagonal angle also makes the overlay slant downwards. Facing North East causes it to angle directly downwards but semi-forwards. It gets more confusing to figure out the more angles you add.