[Cobbiusto]

From the main menu, choose to create a new custom game.
- from the next menu choose to create a fictional league.
- in the next menu choose the number of divisions and teams per division you want.
- in the next menu click the button that says "switch to historical team selection".
- then just choose the year and team you want in each spot.

Hope that gets you to the spot you want to be. OOTP is amazingly customizable, but that sometimes makes it really complicated to jump through all the right hoops. Usually though you can come up with almost any combination of ideas imaginable.

(this is actually for playing a whole season - for tournament see below)