The projector has a 3 foot vertical lens shift. It will be slightly mounted on a down angle to add another 2-3 feet. There will be keystoning, but we should be able to overcome it and make it pretty close.

The balcony has an iron fence, so it would be difficult to reach round and clean the glass, but it would be possible.

I've written to the company that makes the outdoor box to see if they've tested it and how their glass works.