Borranis were used ( Cross on V7 Sport, then Record) on all spoked big block models until Guzzi started using cast wheels or Akronts. I have seen Cali 2, T4 and G5 both with cast wheels as well as spoked wheels.. The Akronts were used on 1000S, and Cali3/1100 from the end on the 1980's Also by then Moto Guzzi had gone to a 5 bolt brake rotor hub. and flat floating rotors .
I was getting a Ducati Bevel 900GTS fitted with alloy rims in the mid 90's and was told by the good folks at Buchanan's in LA that the Akronts were actually stronger and a bit heavier than the Borranis. If you have the 6 bolt hub , most likely the rim was replaced at some point as Borranis became a little thin on the ground and Akronts were better priced anyway.