Evan,
I wish I knew of FM when I got asked.
I would add to the mix that in addition to site scouting, have a list of shots to take, including (and most importantly) a coordinated and timed plan for the formals (who gets shot with the B+G and when). If the answer you get to a request to go over such things meets with "oh, I'm sure you will do fine", Run! Run fast and run far.