Series 3 quarter panel rivet locations

[slowpatina]

Some 1972 Series 3 short wheel base 88's have only three rivets (not talking about spot welds) across the rear quarter panel above the wheel well from the rear of the truck to the door, whereas other's in the same year have the three clusters of rivets (7, 3, 4 in each cluster) from rear to door. Is this just a manufacturing change by LR at some point during the year?

[charles1943]

These were the heads of rivets for the seat belt anchors

[jimrr]

7, 4, 5 on my series 3 (last new one sold in lower 48) the upper seat belt anchor has 4 rivits ( at eye level, the 7,4,5 at knee height) and one additional nut showing, the other side of which is under the aluminum trim hiding the aluminum body. the lower seat belt anchor is galvanized steel bolted to the body with 3 bolts.