Kontact subtly touched on that in the second post when he pointed out that the OP should be looking for an ISO spindle for his Super Record crankset. The OP's Campy cranks are made for an ISO-tapered bottom bracket spindle. Shimano cranks and bottom brackets use JIS. The taper angle is the same, but ISO spindles are a bit skinnier at the end.

It is possible to mix and match somewhat, but you need to be aware of the fitment considerations to compensate. Sheldon Brown's site, linked below, touches on that.

https://www.sheldonbrown.com/bbtaper.html