I decided to document my first effort at fender flares. I was pleased with the result.
Unflared Tamiya Lotus 30 fender
Attempting to duplicate the look and width of the Lotus 40. The Lotus 30 is on the left.
Liquid glue, snips, 0.040" styrene, and misc.
Strip needs to be about this wide.
Snip - snip - snip...
Rough-up both sides of strip, and inside and outside of fender (the black stuff is carbon fiber reinforcing in the nose).
Pre-curve the strips.
Make strip-loops, secured with alligator clips. Expand loop in place for tight fit. Liquid glue outside and in (where accessible). Hold in place until secure. Doesn't take long... hair dryer speeds process.
Second front wheel done.
Allow to dry completely... rears were done earlier.
Hard to see in picture, but inside was epoxied for strength, heated with blow-dryer to improve flow and hasten cure. I did each side of the car separately, and allowed to cure standing "on edge", so epoxy would pool around styrene ring.
Excess removed from inside with Dremel.
Outside contour filed to shape. Use a good file... a large file. 
I read somewhere that talc added to filler improves "sandability", so I used equal volumes of epoxy and talcum powder (check the ingredients... we want talc). Seemed to work okay.
It doesn't require much epoxy for such little flares. Nothing beats a finger to wipe off the excess. Again, do each side separately and cure with body "on edge", to control epoxy "creep". A plastic eraser makes a great model-sized sanding block.
Sanded and primed.
Ready for paint.
The finished insides.
I may update this after paint. 
- James
