lsxponcho

Feel free to flame on if this is a dumb question; but does anyone have pics of their stock 4.8 pistons? I tore down one that i've recently acquired to build, and noticed some stamping that i can't seem to find on the interwebs. I'm wondering if the number 7137 refers to some sort of part #, and the 20 below it, maybe meaning .20 over bore? The other numbers mean nothing from what I could find either. I could be retarded and all the 4.8's are like this, but the last 5.3 I tore down had no stamped id numbers on the pistons like this, not that it means anything possibly. Here are some pics. Thanks in advance.