I went and tried to find that part #.... my mistake, they were the Lime Fire baffles from CarChemistry. I had Tig'ed the baffle to a insert that just slide up inside the pipe, using the included collector flange. I TIG'ed the baffle to a piece I made that was the same dia. and same taper as my pipes, then I got my 4 1/2 grinder with a flap wheel and rounded the collector flange so it would fit in exactly agianst the output side of the baffle then I gave it 4 heavy duty tacks, fastening it to the baffle.
I slide it up in the pipe, 2" in from the end, drilled my holes to put my bolts on.
As you looked from the end, the exhause came thru the center hole, where the perforated tube is located, but also, I welded that collecter flange to the baffle, I also used my plasma to cut out those 3 flange holes.
So, looking up into my pipes, I had 2 headers, 3 cylinders ea., you hade a center hole, then, 3 smaller holes close to the edge of the diameter of the baffle.
Hey, it sounded good, like a pair of big diameter CherryBombs.