Help identifying headers

I've got a set of double-wall F/C headers that I'm not totally sure what they fit. The don't fit Veney's (which I originally thought they did) but the three inside pairs of holes match the studs on some Stage 5 water heads, along with one stud on the ends. Is this the same basic pattern as early Brad fuel heads? I know most of those have similar patterns, just don't have anyone in my area that I could physically match them up to. Thanks for any info.