Re: For those with AFR 195 eliminator heads
I don't think there is any such thing as an NPS fitting. It would leak anyway, nothing to tighten it up against or into. Call AFR and ask them to send you some non-leaking NPS fittings, see what they say. I'll bet it's not "Sure, we'll send a few right out."
GO back to the hardware store and buy a 3/8" NPT tap. Tap the holes out 2 threads at a time till whatever you're screwing in goes in as far as you want.
Tom Terrific or Terrible Tom, depending on the phase of the moon, passing cosmic rays or other factors not fully understood except by my wife.