And, if I may take a peek ahead towards next Friday:
Strong favorites to advance to the quarterfinals would be Pella, Heelan, Carroll and Xavier. I am less certain of the other four winners, although I have a good feeling about Creston and Solon. The Carlisle-Washington and Gilbert-Dallas Center Grimes games look like tossups to me.
If I'm right about those first four, surely Carroll at Heelan would be one quarterfinal (if I read the postseason manual correctly, home field for third-round games this year is determined by 1) district finish; 2) district record; 3) head to head; and 4) reverse alphabetical order). I think the winner of Solon/West Delaware would be at Xavier. After that, who knows? Somebody goes to Pella, probably Washington if they win. If Creston wins, they likely play Dallas Center Grimes, if they're a winner too. If it's Creston, Gilbert, and Washington that advance, then you could see Creston-Pella and Washington-Gilbert.
Just a lot of variables, still. If forced to make a Kreskin-esque prediction this morning, here's what I might project for next Friday (all of these are rematches, by the way, so head to head breaks any district finish/record ties):
Carroll at Heelan
Solon at Xavier
Creston at Dallas Center-Grimes
Carlisle at Pella