No published data from manufacturer on Mast height. The number was given to me by the PO. That's why I checked. Well, one reason I checked. Just went under a 65 foot bridge with the water mark at 65 - I was just about at high tide - and I had lots (realatively speaking) of space above the top, as best we could see.....I hope you followed the "woodworkers code". Measure twice, cut once. If it is 60 feet including the whip antenna, then that means your "published" air draft is about 3 feet more than your measured height from the waterline! That is a huge disparity and not to be a Debby Downer, but I'd check that carefully I am a little skeptical at a 3 foot difference from published to measured. I'd expect more in the line of a few inches or a foot at most, mostly due to actual loaded displacement in your current condition to the assumed load for the published air draft. Just saying, something does not seem right. There should be some published inches of draft change per 1000lbs of load for your boat. It is part of the design calcs and sailboat data commonly provided.
Did the PO shorten them mast? It is hard to believe that you have enough weight on board to lower your float line by 3 feet. That would be pretty obvious. Was the "document" just something you got from the PO or is it from published sailboat data for your year, make and model?
dj