I'm looking to get a new exhaust for my 96 300 90 and while browsing to get an idea of price etc, I have noticed some are to fit all 300's while others claim to be 96/97 only or just state 'early 300tdi'. I know mines an early one because it has no EGR from new, but are the exhausts actually different?

It is the last hanger on the tailpipe that is different, some point inwards and others out (can't remember which is which off-hand).
So yes, unless you order a universal one with the twin hangers then it won't fit.
If in doubt, take a look at yours and then inspect parts photos on the various websites, you will soon see the difference.

Personally I like the BP ones, made by Bosal and are good for 5-years while still being very reasonable cost.

Thanks. If thats the only difference then thats fine as I'm a welder so I can move mounts if needed.