I mounted a 6 led string similar to Roger's although I mounted it directly to the fender. I filled the "V" with hot glue plastic so it provided a solid mount.  I picked up a pair of the lights for $31 on Ebay.  Works well, but does block some of the headlight to the ground to the sides of the wheel.  No big deal.  Advertised as 1770 Lumens - 18 watts. 30 degree beam width.  20 would probably be better, but definitely adds to the visibility and night lighting.