If you look at the standard cluster picture and the 300km one you will see that the plastic covering around the dials is different. one is a series 1 and the other is a series 2, im not 100% sure which is which but thats the main difference on the front.
On the back with the wiring, the only difference is you have to add two cables for the airbag (series 2) so if you want it in a series 1 with no airbag you remove the cables, that simple. with all this said one of the dials is from a series 2 and the other is from a series 1 so i can mix and match them to fit your car if you like. it is very easily done.
Cheers,
Bernard.