I have the 68 Fisher body manual. It does not the dimensions of the placement of the holes. But. no matter which emblem ( Chevrolet, Caprice, SS427 or Impala super sport) they all go in the same 3 holes punched in the lower right corner of the deck lid. If you look on the inside of that corner, there are pre-made access holes in the support frame to attach the retaining nuts of the emblem. If you don't have any holes showing on the outside, they must have been welded over or have Bondo filling them. you will see where the original holes were. Don S
Of course my advice is obvious, but just for the say so, check on the backside of the lid to see if you can see any bondo in the filled in holes. If there, carefully drill them out with a real small bit from the inside, then carefully drill them to size from the outside.
-Parting Out over 75 '58 to '73 Full Size Chevy Cars-
-National Impala Association
-Vintage Chevrolet Club of America
I went out and looked at the trunk lid. You are right. They filled in one hole with body filler and the other 2 were welded up. As you look up into the back side of the trunk panel there seems to be a long way to the top panel. I don't think a drill bit is going to be long enough to drill it out.