Thanks for your comments! I just got off the phone with Monaco tech support. I tried to reach them yesterday but never did. I explained the problem of making the ducts line up. They said that it was a real PITA! They told me the horizontal duct running from front to back is just styrofoam with a foil coating. I am going to cut the duct completely into on each side of the opening, install the top unit, attach the discharge duct, then put the duct back in place and tape it back together with foil duct repair tape! They say this should work fine! :B
