hmm. To play devil's advocate. Shimming in this fashion would introduce length since the shims would interfere with the parts fully seating. Second, while minute that same effect weakens the threaded joint because it is not fully seated.
conversely, as an alternative using real metals why would you not use super thin bronze and/or copper tape?
ultimately none of the above is absolute accurate, which is why we are including the aluminum windvane.
The original feature is paint accumulation at the corners...
It's not a filet of paint accumulation just at the corners. The entire upper and lower surface above/below the windvane has the bronze/antique-gold/aged/brass color:
No worries if you guys aren't reproducing this feature. I can order a sheet of bronze and get the upper/lower disks punched out myself to slide over the upper/lower windvane areas.