I'm in the process rebuilding my Interstate.
I have three strips (red, yellow, blue) in my Pods aimed to shine through the grated holes.
The red comes on with the brakes, the yellows when I signal and the blue with a switch.
As well, I have blue strips under the tank lips on either side, both carb covers, below the saddle bags (also R,Y,B), above and in front of the rear fender and several embedded in acrylic.
I'l post pictures when I am done. I do have pictures but all are too big to post in photstash.
This pick is old, before adding any LEDs, it shows some of the acrylic work. The acrylic is also between the master cylinders and their covers.

All my LEDs are hidden.
I got most of them from
www.besthongkong.comThey make a water proof strips that I use 'house hold Goop', otherwise known as 'ShoeGoo' to attach and keep in place. ShoeGoo is AWESOME for wiring placement a smal dab can prevent vibration and is water proof.
Best regards,
Glenn