Windscreen escutcheon plates

The windscreen has been on and off more times than I care to remember, It's now on for good, well the legs are anyway. Part of the final fitting includes filling the gaps where the legs pass through the body with silicon and then fitting these stainless steel escutcheon plates over the top. I've not tackled the silicon yet but the plates have been subtly bent to match the curvature of the body and and the fixing holes drilled and tapped. Rather than use self tappers or bolts through the bodywork, I've cut a thread into the fibreglass which some stainless steel button heads will screw into. There's no strength required to hold the plates down so this should be more than adequate and look a little better than self tapping screws.