Sorry, bowtie, I did mention it in my last post, but I didn't respond directly to you.
Yes, it HAD a spark arrestor when I got it, but that must have fallen out when the muffler rattled loose, because it's not there now.
No extra ports, just the guts removed.
I would consider putting the guts back in the muffler as the muffler studs and muffler tighten on to it. Add some holes to the sides of the piece in the muffler.