I recommend you search and post this question in the main tech forum. Other's have done a big renovation of their AC without necessarily duplicating the C2 system. The biggest issue is getting enough airflow to the front wheel well condenser, the airflow of the 964/993 is much different than on Carreras.
An issue with "duplicating" the 964 AC system is the tremendous difference in the ventilation system. It's as complicated as all getup.
These are for a 993, but give you some ideas:
Evaporator
Auxiliary Oil Cooler (so you can see the inner fender plumbing/fan arrangement
Another view of the
AC condensor/fan