The back end of my chassis seem to be wearing down

i believe its a older version and by the looks of it when it gets a bit more hammer on a outdoor track i could be having problems with the two screws right at the rear, is there any way i could repair it with resin for instance bring the thickness back up again then file and redrill for the srews

as i imagine a new chassis will sting me a fair bit....will post some pics of the problem later..
Neil...