Sean,
7pm might be a touch early, as the Vostinaks and I have a 2:50pm tee time at Crail, and Brad & Glen Rapaport tee off at 3:00pm.
Careful there, Brad and Glen might get a bit impatient and pipe a few tee shots into you three!
Take note of the standard delay - if there is anybody else on the course that late - on the third tee. The rule there is you can't hit from the third tee until the group ahead clears the fourth tee, so it can get pretty congested on that lovely bluff far above the sea.
Have fun - the Balcomie is really a classic! There may not be a harder par 3 anywhere than #13, although #16 is very strong too.
Actually, that's a very strong set of par 3s - #4, #7, #13, #14, #16, #18. Downhill #14 is the easiest of the bunch, but not if the wind is up.