Looking for info on what hardware (screws/clips?) are needed to mount the rear black plastic SR5 style flares. A friend picked some up w/o hardware, front is simple, self tappers into the fender liner inserts, rear doors need clips. But what's typically used for the main rear flare that mounts on the wheel arch? (he's got a base model, so no indications of mounting points on the rear wheel arches) Seems like clip on nuts w/screws, or drill away on the wheel arch?