How are players meant to retry the "Drain Sewers to find Statue" mission to unlock the Turbo JET-Board in Haven City secret?

[awkspace]

I didn't notice that this was a challenge in the secret menu until long after I had done the mission.

[dallmeyer]

level select (it's unlocked as a secret in the original game)

[awkspace]

I thought that level select only allowed you to start a new save, not modify an existing one.

[ManDude]

You don't need to modify an existing save, the secrets are unlocked for every savefile.