Proper Screws for Panel Overlay

[callegro]

Hi guys,

I was wondering if there is a specific screw for the panel overlay in my '67 180D.

I feel that my mechanic put these screws and washers on, but either they are too short in length and due to engine vibrations, they start becoming loose.

Any specific length/gauge that you recommend?

Thanks

 

[BentWing]

 

[callegro]

 

[Tweety]

 

[kshaw]

 

[philiplane]