Have you tried this product?

LED turn signal arrows

http://stores.ebay.com/EURODEZIGNS-LIGHTING-SUPERSTORE

No I have not... but I would like to see some pics if someone has.

Here is a little movie I made of mine in action. There will be a "how to" on this modification very soon..... I promise :o

http://s101.photobucket.com/albums/m69/HondaRidgeline/Turn%20Signals/?action=view&current=100_0045.flv

I forgot to take a picture of the mirror side of the mirror but here is what the outside looks like. You have to watch the movie until the end to see the arrow side on the mirror.

http://i101.photobucket.com/albums/m69/HondaRidgeline/Turn%20Signals/100_0046.jpg