Sorry, I haven't. A project sort of fell in my lap and Ive spent most of my spare time parting out a Super Beetle. Once I'm done with it and can get the truck into the garage again, I've got a buffet of new parts that need to be installed. I'll get back to thinking about ac once that's done.
Well, there's ALWAYS a way, just not always a cheap modification. It might mean - at worst case - fabricating mounts for "any" compressor, and having the refrigeration line end fittings that match that compressor grafted onto the Mazda lines. Don't be afraif to contact Ice-AC in San Diego either (they make AC kits for VWs and others, and are always grafting new compressors onto existing systems, maybe they could provide assistance as well).
If it's a 1971 or 1972 SB, how much for the steering box? And maybe list other parts from it if 71-72...