A Vixen-GP mount shall be mounted on a tripod of an AZ-EQ6. So here an EQ-5 mount meets an EQ-6 tripod. So an adapter is needed.
This one works excellent:
https://www.teleskop-spezialisten.de/shop/Montierung-Zubehoer/Sonstiges-Zubehoer/Geoptik-Adapter-fuer-GP/EQ-Montierungen-fuer-EQ6-Hercules-Stativ::5860.html
Mounting tool:
Open-end wrench 16 mm
open-end wrench 12 mm
Allen wrench size 8
The EQ-6 tripod naked.
Use a 16 mm open-end wrench to remove the pole screw. We will need this later.
The screw is inserted with an 8 mm Allen wrench where the pole screw was before.
Since the central screw is too short, the adapter is screwed on.
The lock nut of the pole screw is removed, otherwise it will prevent the mount from fitting into the socket. The pole screw is fixed with a 12 mm open-end wrench.