Here are couple of more images of the instructions brochure for Dura Ace AX Dynadrive pedals. Note these are NOT EX pedals.
I just took off one of my drive side Dynadrive pedals. I have these on two bicycles.
I inserted the 6mm hex key into the hex on the spindle and inserted the 5mm hex key into thelock-nut on the inside of the pedal body.
The 5m key handle is pointind out over the cleat plate towards the rear of the pedal..
Turning the 6mm hex key CLOCKWISE resulted in the cone loosening. If I keep turning the 6mm key clockwise the cone will eventually separate from the lock nut.
I hope that helps you.
Note that in the image I provided it says that the notches on the left pedal housing are IDENTIFYING NOTCHES. The right pedal housing does NOT have them.
Cheers
Dura Ace AX 1b by
Miele Man, on Flickr
Dura Ace AX 1a by
Miele Man, on Flickr