I needed to compensate, so I modeled up these girthy boys. They are a large and in charge 2 inches long. If you would like them larger or smaller I can remix them or share my meshmixer file.
You can simply pop these on top of your stock valve covers. They should be a pretty tight fit. I didn't use any glue to secure mine on, but a dab of super glue could be used to make them extra permanent.
MG Chemicals PETG