Bill
693 is a good boat, the set up that I used is as follows:-
Mast step, rear pin 3 holes from the back of the step, the other pin then fits in front of the tennon.
Mast set up, with the rig firm, not tight, attach a tape to the main haliard and pull to the top of the mast and measure to the aft outside corner of the deck on the transom. Adjust so this is 22' 6" on each side.
Set the lowers tight.
Then don't touch a thing but sail lots. The boat will do well.
Good luck.
John