Just recived my new japspeed 100cell high flow cat down pipe and cant wait to get it fitted, the down pipe is 3 inch and was wondering how to join it to my blitz nur spec r cat back exhaust. The blitz narrows to 2.5 inch so the flange holes dont line up would i need to get the following from exhausts uk so they mate up?

the 1st one on the list (F1)

ExhaustsUK: Suppliers of Cobra Sport Performance Exhausts