I initially went down the 3Dam adapter route, But your comment "Cant be arsed to remove the Nav" is exactly why i , after one week of using the 3Dam adapter, removed the complete Nav preparation, Took me six minutes, and fitted the XT mount where it was. Looks factory fitted. Clean, and minimal. The Nav mount and 3Dam adapter just isn't right, not mentioning the frequent power disconnections and the fact its more or less touching your helmet.......
I did exactly the same and it’s so much better.