On some Monaco rigs the alternator wiring is unique and replacing the alternator with something else means it will never charge right. Unfortunately you are beyond that possibility. Did any tech ever use a clamp on ammeter on the chassis battery to determine the drain? That is very basic.
My advice is for you to join the Monacoers Yahoo Group for help. Folks there have vast experience. PLUS they can tell you where to go for service in FL with techs that can understand and solve your problems. Even if it starts on Monday this is still a very knowledgeable group.