Don't forget that Campagnolo crank arms changed as well. Early (pre CPSC adapted) had no date code on the back of the arms, it will be marked strada 170 for example, 170 being the length and most abundant. For the first generation BB to work get only cranks with up to a date code of a 6 in a Diamond, marked adjacent to the strada & size. The later will be skirting, or after the change in dimensions where one needs a longer spindle. Complicated? Yes to a point, does require some research, a problem comes with an older spindle BB and newer cranks, one gets poor chainline and or the small chainring hits the chainstay. Newer BB with old cranks puts the rings too far out. And the newer cranks have extra spacing between the big ring centerline and the inside of the arm to allow the later derailluer cage to clear, as it had a skin puncture protection lip. So blame all this nonsense on the CPSC
There are some other identifiers, but one needs some visual reference to compare. I won't get into chainring bolt circle differences, the original pattern cranks will go for too much on ebay to be reasonable anyway.