I recently has a go at producing anti-collision lights on a MiG15 for a customer, used LED's siliconed glued into the bottom of an short aluminium tube, which in turn was glued into a suitable hole made in the wing tip. Once fitted the tube was sanded flush with the wing tip, and a piece of acrylic rod, selected to slide into the aluminium was sanded to a pleasing shape so that is protruded out of the wing tip.

The acrylic rod transmits light very well, and the sanded end 'diffuses' the light - looked good in the end.

marcs