Update for anyone that might have this issue in future. Took the whole assembly out and used a spanner and Allen key to get the bolts out. Absolutely pain in the ass! Fitted both mirrors, they’re great until 40/50mph then they vibrate pretty bad, can still see cars in the mirrors but not the best, probably doesn’t help that there’s nothing in the handlebars now although I can’t tell any different personally. They look good though, might see if I can slide the inserts back in though so see if it helps with vibrations as it’s a pain to pull in the clutch to see behind clearly as the vibrations stop then!