Stock crossover does not have a cat in ABS model post 2010 Roadsters, ONLY in the earlier 2004 -2009 Rocket IIIs.
The stock 'boxy' crossover is not a performance flow improver though!
The cats are in the stock muffler cans and they are very heavy. The Dave Platt slipons should be straight through. no centre baffle but a drilled pierced centre pipe with usually fiberglass packing around to dissipate gas velocity and much , much lighter than the stock cans with cats.
The tunes are in the Resources forum, but I am pretty ignorant about which is best and how to download but it is all there I believe, and many willing to guide you through.
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