The answer is from Nintendo support website at
http://www.nintendo.com/consumer/systems/3ds/en_na/3dsambassa...
located at the "HOW TO" topic section
step 1
From the Nintendo 3DS HOME menu, select the Nintendo eShop icon.
step 2
Scroll left and select "Settings / Other."
step 3 (Edit)
Scroll down and select "Your Downloads" to view a list of transactions.
step 4
The NES game will be listed here once it is available to download. Tap "Software Info," and then "Redownload" to begin the download process.
Thanks to me, all the Ambassadors won't be confused and hysterical on Thursday 

