By replacing the back plate with the mounting lug with a flat printed back I was able to add a fare amount of twisting movement to this mount, This will only work with a flat back plate. If the one I made does not fit your indicator, sorry you have to make your own.
Note one of the pivot bolts has part of the head removed so I could get as much travel on the indicator as I could
I have added files for using 6mm bolts and nuts. Living in the USA so I don't have much of a stock of metric bolts and nuts so changes were made with just dimensions of the net and have not been printed and tried. would be interested in feed back