30-04-16, 04:42 PM
Scratch that. Took the unit off the bike. Had to drill out one half of the unit (the base side not the mirror side) to get an M6 bolt through but it's back together and working fine again (a bit tighter now right enough!). So I guess the answer to my original question is yes you can just fit a nut and bolt and have it still work fine, providing you still have the curved spaces and haven't lost them 
