Unfortunately it is impossible to know all the details of your installation to advise on whether or not this kit could be mounted as you desire. The only parameters known for this kit are obviously it is designed to be mounted flush. There is no design spec for horizontal or vertical mounting so that should not be an issue, however we would recommend you consult with a local Lennox technician to advise you directly about installation and functionality questions. This unit does usually ship from stock and can generally ship the same day if ordered by 4pm EST.
Replied on June 13, 2017 by Ron from Industrial Stores