Emergencies, Part I

You've been invited to play for this important event on a wonderful pipe organ with which you're very familiar and have performed upon many times before.
You've prepared some wonderful organ music from the literature, know it thoroughly, and arrive an hour before, loaded for bear.
There's only one problem. You find out that the roof leaked a week ago directly over the Pedal division, carrying rain water and filth from the roof down into the pipes and chests, rendering them unplayable until the organ builder can be summoned to make the needed repairs.
You need a big sound, and you want your playing to sound written. And that beautiful pedalboard under your feet, for the time being, is useless. The organ builder has disconnected it until repairs can be made, and manual to pedal coupling is impossible. The manuals have to do it all. You've got an emergency on your hands.
Now what.
Then you remember, you've got this problem solved. You heave a sigh of relief. You've got some of those free scores from this web site with you.
And you learned them.
You're saved.
(con't in Part II)