I think there is a picture (among a thousand others) on the Windpilot site windpilot.com. Whatever the windvane, some sort of mounting must be contructed to hold the tiller pilot so its ram can be attched to the stub of the windvane.
There is a good picture on page 129 of Geof Pack's book "Bluewater Countdown".
I posted a similar question on another site some time back and one of the respondents pointed out that on his boat, the wash from the propellor meant that the servo paddle was working in extremely turbulent water which in turn caused so much vibration in the rest of the vane gear that he was afraid that it would destroy itself so he could only use it under sail and not under power - which rather defeated the object of the exercise! Others said that it worked well.........