I would try 4-1-2-1-2 Narrow diamond. Used this recently against a way stronger team using 4-5-1.. It was a match i honestly thought i wouldnt win, I was correct but never lost, drew 2-2 away.. Had more shots and a bit more possession. Overall i was the better team that match..

Regarding the players out of their positions, if you put a player out of his primary position and you happen to draw or lose the match, his morale drops drastically.. Try playing them in their right positions. Good luck with the match. Post the results.