I'd prefer a windscreen decal. That's where I'm putting all my decals from companies I use products from (I.E. Competition Werkes for my fender elim, or [eventually] Area-P for my exhaust). I'm planning to get a double bubble, so I'd throw the Ninjette.org sticker right up at the top. Dimensions I'd suggest (windscreen decal): about 1.5" by 4"
Should give plenty of space for logos. Lemme know how it turns out.