Congrats! My first RX-7 was an 88 vert. I loved it and the only reason i sold it was to build my house.
A few facts to know:
Yes, Mazda made Turbo II convertibles, named Savana, only in the Japanese, European, and Austrailian markets. There are a few in the states.
If you are planning to mod the car:
Don't even bother to think you can add a turbo to your car. The 6-port motor will only have nominal gains in HP. It is FAR cheaper and easier to just swap a TII drivetrain in.
You cannot put a straight through exhaust on it, as the 6-ports need back-pressure to open.
If you car still has the stock pre-cat and cat, I would recommend removing the pre-cat and install a down-pipe, and a high flow cat (if neccessary). These will actually extend the life of your motor due to heat and pressure relief.
The wiper switch and the A/C controls (logicon) are notorious for taking dumps. Dealer prices on these components are insane. Some people on Teamfc3s and RX7club forums actually repair them.
The vert top motor is also insanely expensive. The top will operate manually with no problems.
If you have any questions about your car, or need advice, let me know.
Again, congrats!
Michael