The Fulsac Baffles where you screw into the baffles to hold them into the pipes are set further back than the stock baffles. Therefore you can't connect the inner ring to attach the black tips. If that makes sense.
I'm puzzled by that, YB. I assume you're talking about the 4" ones? They must differ from the 3½" ones, I guess in the way that there were two different fixing methods for the old 3½" tips - one (like my new ones) where the tip slides into the end of the muffler, and the three bolts that you screw in pass through the tip and fasten the baffle in. like 65115-98B. The other, for mufflers where the baffle was welded in, like 65259-00, had a ring with three threaded holes inserted inside the tip, so the bolts would again pass through the tip, holding it in.
Assuming that's how it is, why can't you just use a nut on the inside instead of the ring? Pleanty room to get a wrench in to hold it.....

Jim