Installing window Air Conditioner?

Question:I am installing a small (5,050 BTU) window unit in my daughters clubhouse. I will be cutting a hole in the wall and framing the hole to mount the A/C. Should the A/C be mounted level or should it have a slight lean toward the rear of the unit??

Answers:
Slight lean towards the ground for water drainage, Make sure you do support the A/C with support bars.