A little exhaust work, all from recycled items except for the four 6" splices where I used new 2" pipe to overlap in both directions.
Downpipe section:

Splice to "H" or "X" pipe section:

Bend to dual in/out cat:

Complete unit:
Downpipe section:

Splice to "H" or "X" pipe section:

Bend to dual in/out cat:

Complete unit:

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