Just a simple 3/8" wide strip of aluminum in the shape of the letter J. Attaches to the bolt that holds the gauge cluster behind the tach. One wire to ground and one wire to the hot of each turn signal (3 total). The pic is the original one I had with small led. The second one I made has a led that's twice as big/bright.
The comment I usually get when discussing the "Geezer" signal reminder is "I just remember to not forget to turn them off." Another obvious piece of advice is "Buy low, sell high". My 1982 Suzuki has self canceling, go figure.
I wrapped the original with black tape, I think I used shrink wrap tubing on the newer one so no wires are exposed.
Oh yea, you need two resistors (for one way current direction) on the hot wires. Only a few dollars worth of parts.