I told Darryl about this Sat so i thought i'd do a post. There's a member on the miata forum that is ordering (miata) parts from japan. Here's one of the sites:
http://www.tsj-freight.com/jpg/thche...miata/jubiride

I am considering ordering the BP alt and waterpump pulleys....here's the major CATCH:

OUR BP Pro use a V-BELT for the alternator whereas the BP miata uses a SERPENTINE belt for the alt. Thus, the PULLEYS are DIFFERENT.

OK here's the lowdown on the Miata's :the 1.6 miata uses a V-BELT on a SMALLER alt - they changed to a LARGER alt and a SERP belt in 94 when they started using the 1.8....that makes me *think* that they could be interchangeable...

Now, Darryl put a larger V6 alt (which bty also used a serp belt) on his Pro, but he made his stock v-belt pulley *fit* the larger alt

okdoke.....stop breath think....now reread

THE CATCH IS THIS: In order to use these pulleys, you'd have to swap in the 94+ Miata alternator AND crank pulley....BUT i'm not totally certain it would work....IF it would, then you *could* get the Miata UR underdrive pulley spinning these as well....