On the build sheet, block 44 says "Hydro Pierce". What is that? (The code for my 1971 Cutlass is "G-1S".)

 

That's an interesting question. On 1970 Build sheets, the Hydro Pierce box is #56. (Box #44 is for paint codes: lower, upper, stripe, and wheels.) Note that sometimes there are also small difference between boxes depending on the plant.

Anyway, I have no idea what Hydro Pierce is. I looked at several build sheets, and the codes in this box are all over the map.

Anyone?

 

All the emblems were attached with speed nuts on posts that went through the body sheet metal. I believe that Hydro pierce is simply a term used to describe the holes that were left by the template drilling for various emblems. Back in the 70's it would be very impressive to think that they actually used water to cut metal wouldn't it? So - Pierced in a pattern according to Jig design is my submission.