I made a slight tweak to the recipe as I didn't have orange bitters so decided to add a little Luxardo Aperitivo instead (I thought this closer than the Australian Bitters alternative I had).
I made a mistake and went for my usual stuffed olives garnish, so removed and added orange zest instead - it didn't seem to suffer too much!...
I will be trying the same cocktail using blanco vermouth which ought to look more like your typical martini.