Thanks Tracy.  I'll have to use an aftermarket regulator, since I have to use
an aftermarket secondary rail.  I'll limit my shopping to the type you
mentioned.  

Cheers,
Rusty
> Most builders use the stock Mazda regulator.  If you use an aftermarket
> part, be sure to get a three port type with a connection to manifold
> pressure to adjust fuel pressure depending on manifold pressure.
>
> Tracy