If you're going to put a 9 speed group on it, the chainrings will definitely need to be replaced.
FYI - I was putzing around starting to assemble my 760 tonight. The Campagnolo Chorus RD stop screw doesn't contact the part of the dropout that normally limits rear derailleur movement. I though I had everything I needed, but evidently I'm a part short. Just giving you a heads-up, as this might possibly happen with your new 105 group also.
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