Let's figure this out logically...
The e-ticket can only be in Main Street, USA, Liberty Square, Tomorrowland, or Adventureland. Remove Main Street and Liberty Square from the list, and you got Adventureland and Tomorrowland.
Now, there is an E-ticket PAD in Adventureland, most likely being built on wetlands outside the "berm" and connected to Adventureland a la Indiana Jones Adventure at Disneyland.
In Tomorrowland, you can build on the Main Street backstage parking lot, or you can build on the retention pond/Skyway plot that they built Space Mountain on, way back when.