[Le Grande Orange]

Originally Posted by Elektranaut

How was the world series organised in this set up?
Indeed how would it have been if the PCL had become a Major League

That was one of the issues which worked against a third major league in real life.

For what it's worth, Branch Rickey floated a three-way World Series idea in the Aug. 23, 1959, issue of The Sporting News in connection with his Continental League. Below is the relevant portion of the article.

According to Ricky, the 1963 series will be a round-robin. This, he says, is how it will be handled:

"It's October, 1963. The Yankees, let us assume, win the American League pennant, the Chicago Cubs prevail in the National League and the Houston Continentals win in our league. The series opens at Yankee Stadium with New York playing the Cubs."

With that settled, baseball's elder statesman poured himself a second cup of coffee, relighted a well-chewed cigar and outlined the following schedule for the next five games of the series.

Game No. 2—New York vs. Houston at the Stadium.
Game No. 3—Chicago vs. New York at Chicago.
Game No. 4—Chicago vs. Houston at Chicago.
Game No. 5—Houston vs. New York at Houston.
Game No. 6—Houston vs. Chicago at Houston.

"What a lovely thing that will be," the 77-year-old Rickey said. He brought his right hand down hard on the table and the dished jumped.

"Judas Priest, I'd love to see that. The team that loses four games first will be eliminated, but just think of it. Each team will play two series games at home before it can be eliminated. The others will continue until one wins four games.

"I figured out this plan mathematically and it would be impossible for the series to be decided in less than eight games or more than eleven. Anyone who cares to check will find out it's correct."

ETA: After quickly playing around with Rickey's plan, I'm not sure it actually works as it was described, unless there were some details omitted from the article.

For example, using the given schedule, it's possible for a club to win four games without either of the other clubs having lost four games. See the example below; teams in bold are the winners of the game.

Game 1: CHN at NYA (NYA 1-0, CHN 0-1, HOU 0-0)
Game 2: HOU at NYA (NYA 2-0, CHN 0-1, HOU 0-1)
Game 3: NYA at CHN (NYA 3-0, CHN 0-2, HOU 0-1)
Game 4: HOU at CHN (NYA 3-0, CHN 1-2, HOU 0-2)
Game 5: NYA at HOU (NYA 4-0, CHN 1-2, HOU 0-3)
Game 6: CHN at HOU (NYA 4-0, CHN 1-3 HOU 1-3)

Presumably, if something like this happened the Yankees would not yet be considered the Series winner since neither of the other clubs had lost four times yet. Maybe Rickey meant a club had to win five games to be declared the Series winner?