That is a seriously thick walled pipe. The OD was about 2.8" from what I remember, normally that qualifies as 2.75. The OD was still .25" bigger than my '95 though which makes me think that the gen 2 engine gained some HP over the gen 1 because of the better exhaust.
So to get this straight, we have two 2" pipes joining into a single 2 1/2" that joins into the 2 1/2 inlet cat? Did you change your cat? I'm debating on whether it is worth it. I'm planning only moderate mods to my car (either intense step one or two) I remember when I changed the cat on my '95, I lost a tiny bit at low RPM and gained slightly at high RPM. No net gain.