Yesterday, I had the OEM exhaust on my H22A8. After much aggro it was off and Phil's old Greddy exhaust was on.
So that's a 4G JDM (I think?) cat-back mated up to the stock UKDM H22A8 exhaust, with the original 39.5cm cat still fitted.
Fitting a regular JDM or UKDM decat will leave it far too short, as you can see it sits in a little bit but that is the norm for 4G exhausts on a 5G, or so I've read. This does mean part of my rear lip might have melted a little bit but it can't be really be seen and the minor length issue will be sorted properly when the rest of the exhaust gets upgraded. I know what I need to do to move it a touch lower from the lip so for now it's a non-issue.
Flange bolt holes needed extending a bit to overcome the difference between UKDM and JDM but with some improv it was done, and a hanger needs moving on the back but the hardcore rubber action holding it nice and tight is sufficient for now.
Aside from stubborn cat fixings it wasn't too bad, right Phil
So a massive, can't even say how much, thanks to @4thgenphil for being a true gent in getting this fitted. I'd like to say I helped but not really
Anyway, a Herculean effort that I'm very thankful for. 
Got me out of a bit of a spot since my old exhaust decided to err... slightly separate... at the start of the week. And I can't go with out saying Phil's mrs makes a cracking cup of tea It looks and sounds awesome, well happy.
Plus the pleasant rumble through the seat base is hot.
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