308 GTB Alternator Upper Mounting Bracket

In the process of removing my alternator, it appears the hardware that secures the alternator to the upper bracket was changed sometime in the past. Table 45 from the Spare Parts Catalog (1976 USA Version) shows item 34 as a "Distanziale" which appears to translate as a spacer. My car had a typical hex nut in its place. Can I use the hex nut or should I try to find a spacer? The hex nut does fit neatly into the hex cutout on the alternator mounting flange (upper left in attached photo). I want to make sure I can securely lock the alternator in place as I understand that the drive belt tension is very high. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login