Ok, here goes. I can't show all the steps since I did this mod some time ago and didn't take pics. The first step was to cut off the mounting ears etc. from the two altitude hubs and square them off.
Attached Image:
Don Wyman
Obsession #1166 18" f/4.5
with Argo Navis and ServoCat
WO Megrez 90 APO
Coronado PST