Does your 23' Safari have a roof vent for the refrigerator, or only an upper side vent?
If it has no roof vent you will not be able to put a taller refrigerator in even w/o the microwave. If it has a roof vent, not a side vent, you might be able to put a larger (taller) one in, it will take some measurements. You will need to consider the slope of the side wall especially to see if there is enough depth available at the top.
I put a taller refrigerator in my '74 Argosy by removing the lower stand the old one sat on, and raising the countertop over the refrigerator area. It worked out very well and I am much happier with the increased refrigerator space. All the old Argosy's had a roof vent. It is only some of the more recent smaller AS units which have the side vent and fan system which are a real problem to work with.