225 connecting rods

The machine shop called today and said 5 of the six rods out of our slant were stamped #5's. I never checked them so new no different. Is this normal?

He said their was as much as 35 grams differance in the rods. That sounds like quite a bit to me. My first slant six build, usualy chrysler rods are stamped 1-8 on the v8's. Just figured the six would be the same. Not that it matters just wondering. Thanks Joe