Riveting doublers onto new wing struts and drilling attachment holes to 7/16. Photo shows the new struts on the left alongside the old ones on the right.
The new struts have a different profile, so are resistant to the in-flight vibration of the old struts. In my case the old struts were misdrilled from the factory, so I implemented the service bulletin and upsized the rivets to 1/4". I takes a large 'bolt cutter' sized rivet puller to set 1/4" SS rivets!