So with all the advice my father in law got from me, from you all, he got an 8,000 BTU Window AC unit and started hacking into the cabinet of his Jayco 1207. Here are some pics: Inside view. Trim will eventually be installed around it for a more finished look. Outside venting. Inside the cabinet. Notice the vent holes. Another inside the cabinet view. The plan is to add some ducting around the side and some fans to push the hot air out and to pull outside arir in.