mine is a harley outer and inner fairing
i used a piece of 7 inch pipe i believe 1" long , took it too a local place with a huge lath took accurate measurements of inside and outside of headlight besile and extended it out about an inch? if you look at my pics real close at front headlight you will notice that theirs a black ring where headlight comes out. i made it so that i can remove whole front fairing and radio in less than 5 minutes but its so handy i never take it off anymore!
just an added thought im gonna be putting my bike up for sale shortly?