Hi all,
Matt & Leesa you are correct - the diesel air-box is a slightly different shape to that of the petrol version.
You still can use this filter however you'll need to do a little modification to fill the slight gap on one side that the filter doesn't quite cover!
robbo1959 unless you have a different filter fitted to your CRD JK (which so far I've been unable to locate) I'd suggest you check it as if it's anything like mine you will have a gap in one corner which could potentially be letting in un filtered air into your engine.
Hope this helps