Exhaust rattle....

[s14unimog]

Ok so here's the gist of it....

I've got an S13 SR in my s14 with the stock turbo setup. I've got a tubular exhaust manifold and an Ebay divorced dump from my old KA-T setup. the rest of the exhaust is a 3" down pipe (no flex section), 3" test pipe, and a Blitz Nur Spec R catback. I recently developed a horrible rattle at 4k RPM. Noticing that my resonator was leaking I decided to remove it all together (thanks to Blitz North America for sending me an 80mm section from a WRX exhaust to get a straight section out of). Fortunately that eliminated the hole in the resonator and bought me a couple inches of ground clearance but it did not fix the rattle.

I am left with a few thoughts...
Could it be that bolt in piece from the divorced dump?

Has anyone ever heard of the packing coming apart in the Nur Spec's Muffler and would it produce such a loud rattle?

Are there some heat shields under the car I need to eliminate or secure better?

Other than the muffler at the Nur Spec tip and the divorced bolt in divider, I can't think of anything thats under there that isn't just 80mm pipe.