Damn guys. So many posts for a simple thing. DevMenu 6.2 is super hard to find and no one can help you with that here since it's part of the Nintendo SDK and not redistributable.
Instead, use Blawr's version of TinFoil and just delete the Application Record for the update and the game. Boom, required version reset. Save data will be unaffected (this may cause issues if the save data for the latest update is not compatible with the version you wish to play).
how is this different from the version of Tinfoil by Adubbz?