[jocko]

Generally speaking, three nub 6 lug wheels are pre-71 C and K 10. And could go all the way back to 1960 or so. Would have to cross check what widths were available when to narrow it down. The backside pic is so dead on center it's almost an optical illusion.. If the area where the wheel joins the center is tapered, that's another indication that it's a pre-71 wheel. If it's not (I just can't tell in the picture), then they may be aftermarket. Or perhaps very early 71?? I've never seen a 3 nub disk brake wheel though - maybe someone else has though.