Could you give us a little more information on the deployment?
It sounds like you would be better off running the QUAD as a sloper. It is 65 feet long if you are operating at the bottom of each CW sub band. If you mostly operate in the phone portion then it will be somewhat shorter. The 10 meter stub is about 16 feet away from the feed point. If you can get the stub horizontal then it would work well as an inverted “L”.
Is your shack window near the house edge? Attaching the box there and running as a sloper would work better. If you give me a number I can give you a call and make better suggestions. Email me direct at qrpm at aol.com.
73 for now,