Congrats on a great find. I put an A/C on the roof of our Caravel
after reinforcing the ribs. On our next restoration, we put the A/C on the floor and it looks better and is far quieter. Warning -- it is a time consuming installation.
See Becky's Thread
for her installation on a Bambi II (essentially the same as a Caravel but one year older). This thread and the links in it were all I needed to copy the idea.