I believe those are pin router marks.
Our guit4ri5t plays 2 pre Ernie Ball G&L's both have the nail holes. Not sure what year they were made though.
Yep, for use with a template for a router or shaper. Leo was still using them on G&L's at least as late as '82,
Yup, my bad, I was reading all about the history of such just yesterday but with only 4 hours sleep after a late rehearsal I got things a little muddled this morning.
Wait till you get to be my age, muddled will be a constant state of mind.