I don't know what the original specs were for the '96. Mine was a new installation, as opposed to a replacement, which is good and bad. I went with the Mermaid Air 9,000 BTU unit for a couple of reasons:
1. The footprint is the same as their 6,000 BTU unit, and considerably smaller than other similarly sized units.
2. They got more competitive with their pricing, once I talked with them.
3. They are local for me (Ft. Myers, FL). As I was going through the installation process, I ended up going over to their shop a couple of times for questions, and they were very helpful.
4. Their turnaround time for the unit was only a couple of days. They build their units on demand, but that was faster than waiting for other, pre-built units to be shipped to me.
I had one problem post-installation. They walked me through the fix in less than 5 minutes on the phone, and it hasn't happened since.
I also talked to MarineAire in Miami. They were very helpful, but the 10,000 BTU unit wouldn't fit behind the stairs or under the v-berth. It wasn't even close, because of the orientation of the air handler.
Good luck. Let me know if you have any questions on it.
FYI, here are some pictures that I posted to another thread yesterday.