Are we sure SL even made a longer spindle for Ital frames? I know I've asked this Q before but I don't remember the answer.

I know TA did not make an Ital spindle. They used the same spindle for 68 and 70, with the cups just being thinner for 68, thicker for 70. The thickness of the cup isn't very obvious to the eye, being only 1 mm different.

I vaguely recall SL did the same, though ya gotta ask yourself, how many Ital bikes have you seen with SL cranks? Nationalistic Ital builders would be loath to put a French crank on if they didn't have to. SL BBs in Ital must be rather rare.

I admit an Ital spindle, if they exist, would explain OP's situation, but I wonder if there could be something else going on.