[Mr Chevorlet]

As far as i know there was a nut welded on the inside that the weld has come loose. if you can drill a small hole close to the threads on each side to the nut then you can spot weld the nut solid to keep it from turning.
oops never mind that fix is for the cowl removed. But if you want to drill a bigger hole on each side of the cowl bolt then a smaller hole to the nut then spot weld it might work.