I couldn't find a thread with this info:

What are the calipers used in these two upgrades:
http://www.thezstore.com/page/TZS/CTGY/classic21k
http://www.thezstore.com/page/TZS/PROD/classic21l/24-5705

Is the second one the one in this thread:
http://woodworkerb.com/home/datsun-240z-rebuild/toyota-front-disk-brake-upgrade/

I purchased and installed the first one above years ago, and I'd like to be able to service it without going through Motorsport Auto (they're pretty tight lipped about what calipers they used).

Thanks in advance,

Christopher

Zcardepot uses Maxima calipers for their rear disc conversions.

Try google, there's some info out there.  Good luck.