Just checked, and yes, it looks like you can delete the update data after it's been installed. Just go to System Settings, then Data Management, choose the drive, then go to game data, and the update should be there. Then just choose it, hit the large delete button, and then you should be able to play through all of Career mode with no issues on the Wii U. Just make sure it doesn't update.
I'm on Chapter 4, and have had zero issues or glitches so far.
The extra Wii U multiplayer modes should work, too. No online though, I'd imagine. I haven't tested those, though.