For Sale: 54" 531 Track Frame & 165mm Campagnolo Pista cranks

As a matter of interest, can anyone tell me what's different between Record Pista and Super Record Pista arms? I know the chainrings were different (record had the inner concentric support ring, super record were fully cutaway like the modern ones), but are the arms different and if so, how to differentiate?

cranks identical, chainrings different
complete sr chainset would come with ti bb axle till it got discontinued