I have one now redundant in my garage
as it came off the 180, sounded awesome and really did improve things.
I used 76mm all throughout and the silicone connector didn't have any issues with sealing on the throttle body. All went great.
I have found a pic of it when new before and during fitting when was on mine.
Bit dirtier now but all as good as it was.
Make a kit up like this one and you'll love it.