Can anyone help (I’ve got a mk1 Fabia). I want to plug my diagnostics machine into a mk 2 (hoping it should still work!) 

 

where abouts is the port for the cable located in a mk2?

Behind the cover for the fuses in the car.  If you are in a right hand drive car down infront of your right knee.

As mentioned above. You will have to remove the plastic cover and kind of duck down to see it but it is there. Just underneath the small cubby hole.