Steering Head Tube Dimensions?
 

Dear fellows,

I would like to find out if any other fork would fit my dear XT.

Does anybody know the dimensions of the steering head tube?
(Like this one: http://www.off-the-road.de/en/News/Steering-head-tube-Aluminium-XT660.html)

...or does anybody have CAD data or would one be so kind to measure...

Kind Regards,
Wauschi