Again this thread is about installing rear bullet light turn signals on a CA95 & CA160. This technique may work on many other stamped metal frame vintage Honda cycles.
I base my signals on the rear fender trom found on the 1964-1966 CA95 Honda 150 Dreams. I just happen to like the look.
For drilling the proper aligned holes I use the CA95 fender trim as a fixture to make sure the holes are correct. This does not mean you can't do your own thing.
I start out with single or dual filament bullet lights. The rear bullet lights are usually dual filament. I like the extra lights in the back. I use single filament lights in the front.
Below is a pic of how I modify the CA95 rear fender trim.
Notice the color code. I use yellow wire as the running light and green(left) or red(right) for turn signals. The bullet lights are rewired to acheive this.