I emailed the ebay seller for more info, very quick response recieved.
Basically the b.box delete is with a 2.5" dia pipe which is fine with the stock exhaust.
If you want to use blueflame products in the future, then you'd need to buy a whole new CAT back system as this would be in 3" dia pipework only.
So two options. Delete pre CAT and add the b.box delete section and keep OEM exhaust,
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OR
A brand new 3" shiny CAT back system!!!!!!!
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